Experimental Investigation and Analysis A Mechanical Properties of Hybrid Pol...IJRES Journal
The hybrids composite has emerged and have the potential reinforcement material for composites and thus gain attraction by many researchers. This is mainly due to their applicable benefits have they offer low density, low cost, renewable, biodegradability and environmentally harmless and also comparable mechanical properties with synthetic fiber composites. In the project natural fiber and glass hybrid composites were fabricated by using epoxy resin combination of hand lay-up method and cold press method. Specimen was cut from the fabricated laminate according to the ASTM standard for different experiments for tensile test, flexural text, and impact test. A significant improvement in tensile strength was indicated by the woven fiber glass hybrid composites. In this hybrid composite laminates banana-glass-banana (BGB) and glass-banana-glass (GBG) exhibit higher mechanical properties due to chemical treatment to natural fibers. So, the hybrid composite material shows the highest mechanical properties. This High performance hybrid composite material has extensive engineering applications such as transport industry, aeronautics, naval, automotive industries.
Experimental Investigation On Mechanical Properties Of Hybrid Jute Fiber Rein...dbpublications
The composite manufacturing has been a wide area of research and it is the preferred choice due to its superior properties like low density, stiffness, light weight and possesses better mechanical properties. This has found its wide applications in aerospace, automotive, marine and sporting industries. There has been continuous lookout for synthesizing composites without compromising on the mechanical and physical properties. In this project, fiber reinforced composites is preparing with jute fibers & glass fiber of fiber length 5-6 mm. The resins used in this study are epoxy. The prepared composites were tested to study the mechanical properties of the composite such as tensile strength, flexural strength, impact strength and hardness.
Study on Effect of Thickness and Fibre Orientation on a Tensile and Flexural ...IJERA Editor
This project presents the study of tensile, flexural & moisture absorption properties of composites made from S-glass, Carbon and E-glass fibre. The specimens are prepared using hand lay-up techniques as per ASTM standard for different thickness 2mm and 3mm and fibre orientation of 30º, 45º and 60º, where an attempt is made to study the properties of composite materials by composing the different materials together to obtain the desired properties by increasing the thickness and fibre orientation. By the variation of thickness tensile strength of hybrid composite is observed for each thickness and is compared with the finite element analysis results. The test ready specimens were subjected to tensile and flexural loads on UTM. This research indicates that tensile strength is mainly dependent on the fiber orientation & thickness of laminated polymer composites. The moisture absorption increases with the fibre, filler content and duration of immersion in water.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Study Analysis & Application of Bio-Composite Smart Materialtheijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
Study Analysis & Application of Bio-Composite Smart Materialtheijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
Experimental Investigation and Analysis A Mechanical Properties of Hybrid Pol...IJRES Journal
The hybrids composite has emerged and have the potential reinforcement material for composites and thus gain attraction by many researchers. This is mainly due to their applicable benefits have they offer low density, low cost, renewable, biodegradability and environmentally harmless and also comparable mechanical properties with synthetic fiber composites. In the project natural fiber and glass hybrid composites were fabricated by using epoxy resin combination of hand lay-up method and cold press method. Specimen was cut from the fabricated laminate according to the ASTM standard for different experiments for tensile test, flexural text, and impact test. A significant improvement in tensile strength was indicated by the woven fiber glass hybrid composites. In this hybrid composite laminates banana-glass-banana (BGB) and glass-banana-glass (GBG) exhibit higher mechanical properties due to chemical treatment to natural fibers. So, the hybrid composite material shows the highest mechanical properties. This High performance hybrid composite material has extensive engineering applications such as transport industry, aeronautics, naval, automotive industries.
Experimental Investigation On Mechanical Properties Of Hybrid Jute Fiber Rein...dbpublications
The composite manufacturing has been a wide area of research and it is the preferred choice due to its superior properties like low density, stiffness, light weight and possesses better mechanical properties. This has found its wide applications in aerospace, automotive, marine and sporting industries. There has been continuous lookout for synthesizing composites without compromising on the mechanical and physical properties. In this project, fiber reinforced composites is preparing with jute fibers & glass fiber of fiber length 5-6 mm. The resins used in this study are epoxy. The prepared composites were tested to study the mechanical properties of the composite such as tensile strength, flexural strength, impact strength and hardness.
Study on Effect of Thickness and Fibre Orientation on a Tensile and Flexural ...IJERA Editor
This project presents the study of tensile, flexural & moisture absorption properties of composites made from S-glass, Carbon and E-glass fibre. The specimens are prepared using hand lay-up techniques as per ASTM standard for different thickness 2mm and 3mm and fibre orientation of 30º, 45º and 60º, where an attempt is made to study the properties of composite materials by composing the different materials together to obtain the desired properties by increasing the thickness and fibre orientation. By the variation of thickness tensile strength of hybrid composite is observed for each thickness and is compared with the finite element analysis results. The test ready specimens were subjected to tensile and flexural loads on UTM. This research indicates that tensile strength is mainly dependent on the fiber orientation & thickness of laminated polymer composites. The moisture absorption increases with the fibre, filler content and duration of immersion in water.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Study Analysis & Application of Bio-Composite Smart Materialtheijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
Study Analysis & Application of Bio-Composite Smart Materialtheijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
Preparation and mechanical characterization of epoxy based composite develope...eSAT Journals
Abstract Increasing concern about environment has made scientist and engineers very eager in their search for environmental friendly materials. So lot of research is going on today in the field of material science to develop newer materials. Natural fibers are getting much attention of researchers, engineers and scientists as reinforcement in the polymer matrix to develop natural fiber reinforced polymer composites. In the present work an attempt has been made to develop natural fibers reinforced polymer matrix composite. Advantages of using natural fibers are density reduction, cost savings and less weight to strength ratio. Composites with 10, 20 and 30 wt % coconut shell powder epoxy composites have been fabricated using Hand layup technique. Mechanical properties of these composites have been analyzed in detail. Keywords – Epoxy based Composites, Hand layup technique, Tensile strength, Flexural strength.
Analysis of the Flexure Behavior and Compressive Strength of Fly Ash Core San...IJERA Editor
In this paper, commercially available Fly Ash and Epoxy is used for the core material, woven glass fabric as reinforcing skin material, epoxy as matrix/adhesive materials used in this study for the construction of sandwich composite. Analysis is carried out on different proportions of epoxy and fly ash sandwiched composite material for determining the flexural strength and compressive strength, three different proportions of epoxy and fly ash used for the study. Those are 65%-35% (65% by weight fly ash and 35% by weight epoxy resin) composite material, 60%-40% and 55%-45% composite material. 60%-40% composite material specimen shows better results in the entire test carried out i.e. Flexure and Compression. The complete experimental results are discussed and presented in this paper.
STUDY ON THE INFLUENCE OF FIBER ORIENTATION ON PALF REINFORCED BISPHENOL COMP...IAEME Publication
The main advantage of a composite material over conventional material like a monolithic metal is the
combination of different properties which are seldom found in the conventional material. In recent years natural fibers
appear to be the outstanding materials which come as the viable and abundant substitute for the expensive and
nonrenewable synthetic fiber. Pineapple leaf fiber (PALF) is one of them that have also good potential as reinforcement
in thermoset composite. The objective of the present work is to investigate the effect of fiber orientation on the mechanical properties of PALF reinforced Bisphenol composite and explores the potential of using PALF as reinforcing
material.
Thermal conductivity Characterization of Bamboo fiber reinforced in Epoxy ResinIOSR Journals
Over a past few decades composites, plastics, ceramics have been the dominant engineering material. The areas of applications of composites materials have grown rapidly and have even found new markets. The current challenge is to make the durable in tough conditions to replace other materials and also to make them cost effective .This has resulted in development of many new techniques currently being used in the industry. While the use of composites it is clear choice in many applications but the selection of material will depend on the factor such as working life, lifetime requirement, complexity of product shape produced, saving the term cost. The availability of natural fiber is abundances and also they are very inexpensive when compared to other advanced manmade fibers. The primary advantage of natural fibers are low density, low cost, biodegradability, acceptable specific properties, less wear during extracting as well as manufacturing composites and wide varieties of natural fibers are locally available. The main focus of this investigation is to determine the thermal conductivity of bamboo fiber reinforced in epoxy resin composites. The test samples were prepared as per ASTM standards using simple hand-layup technique at different fiber weight fractions (10%, 20%30%, 40%50%, 60%). Thermal conductivity (K) of the composites material were determined experimentally and is validated by the results obtained by rule of mixture, E-S model and also by finite element modeling
MECHANICAL CHARACTERIZATION OF BIO-FIBRE AND GLASS FIBRE REINFORCED POLYESTER...ijceronline
Composites are versatile and convenient in diverse application such as automotive and aeronaut industry, constructional materials, civil and military applications and many more. Natural fiber composites are currently being used in mostly non-structural applications [1]. Natural fibers are being widely used to substitute artificial glass and carbon fibers in polymer composites. The aim of present work was to focus on the hybridization of natural fiber (jute) and synthetic fiber (E-glass) with polyester resin for applications in the aerospace industry [1]. The mechanical properties such as tensile, impact, flexural test and water absorption rate of hybrid glass/jute fiber reinforced polyester composites were determined. Laminates were fabricated by hand lay-up technique [2]. Then the mechanical properties of lamina prepared with different compositions of natural and synthetic fibers are compared. Total fiber weight fraction was maintained at 50%. Specimen preparation and testing was carried out as per ASTM standards [1], [2].
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Influence of Carbon & Glass Fiber Reinforcements on Flexural Strength of Epox...IJERA Editor
Hybrid composite materials are more attracted by the engineers because of their properties like stiffness and high specific strength which leads to the potential application in the area of aerospace, marine and automobile sectors. In the present investigation, the flexural strength and flexural modulus of carbon and glass fibers reinforced epoxy hybrid composites were studied. The vacuum bagging technique was adopted for the fabrication of polymer hybrid composite materials. The hardness, flexural strength and flexural modulus of the hybrid composites were determined as per ASTM standards. The hardness, flexural strength and flexural modulus were improved as the fiber reinforcement contents increased in the epoxy matrix material.
INVESTIGATION ON MECHANICAL PROPERTIES OF HEMP-E GLASS FIBER REINFORCED POLYM...IAEME Publication
Natural fiber composite is currently a leading module in the world of composites. It is due to many of its features such as freely available, easy processing, low cost, ability to replace usage of Glass fiber (Synthetic fiber), better strength properties and ecofriendly. They find useful applications in various fields from domestic to automotive sector as of now. Natural fibers with good content of lignocellulose, low density, and better elongation percentage are chosen for manufacturing of composites of above mentioned applications. Unidirectional & Continuous natural fiber composites are said to be anisotropic and having predominant mechanical properties.
Composites are engineered materials made from two or more constituents with different physical or chemical
properties, which remain separate and distinct within the finished structure. A fiber is a material, which is made into
a long filament with diameter generally in the order of 10 microns. The aspect ratio of length to diameter can be
ranging from thousands to infinity in continuous fibers. Increasing worldwide environmental awareness is
encouraging scientific research into the development of cheaper, more environmentally friendly and more
sustainable construction and packing materials. For environment concern on synthetic fiber (such as glass, carbon,
ceramic gibers etc) natural fibers (such as flax, hemp, jute, kenai) etc are widely used. Industrial hemp fiber is one
of the strongest of the natural fibers available and possesses benefits such as low cost and low production energy
requirements. The primary objective of this research is to fabricate the natural fiber composites with suitable
processing/manufacturing methods and to examine the mechanical properties when subjected to Tension, Bending
and to compare & contrast the results with the available literature. In this research work, hemp fiber reinforced
Epoxy matrix composites have been developed by hand layup method with varying process parameters, such as
coupling agent(with and without compatibilizers) and different fiber percentages (10%,20% and 30% by weight).
The developed composites were then characterized by tensile test and flexural testing. Results show that the tensile
strength and flexural properties increases with the increase in fiber percentage. However after a certain percentage
the tensile strength decreases again. Compared to untreated hemp fiber, no significant changes in the tensile strength
have been observed for treated hemp fiber reinforcement. The flexural strength / modulus of the composite were
higher compared to pure epoxy for all filler/fiber loadings.
Fabrication, experimental investigation of jute fiber reinforced epoxy compos...Adib Bin Rashid
A special type of jute fiber woven mat was introduced by a hand loom. Epoxy jute
fiber composites were fabricated using the woven fiber mat. A series of jute-hybrid epoxy composites based on the arrangement of the direction of jute fibers, and additional material were introduced to ensure the elevated mechanical properties of the composites. Improved
mechanical properties were found in some cases of hybrid epoxy composites. It is discussed that the mechanical behavior is related to the fiber orientation, types of additional materials used in hybrid materials. The purpose of this study is to propose a simple technical method to prepare woven jute fiber mat by hand loom, and to produce epoxy jute fiber, hybrid composite materials to exhibit the elevated mechanical properties.
(APA 6th Edition Formatting and Style Guide)
Office of Graduate Studies
Alcorn State University
Engaging Possibilities, Pursuing Excellence
REVISED May 23, 2018
THESIS MANUAL
Graduates
2
COPYRIGHT PRIVILEGES
BELONG TO
OFFICE OF GRADUATE STUDIES
ALCORN STATE UNIVERSITY, LORMAN, MS
Reproduction for distribution of this THESIS MANUAL requires the written permission of the
Provost and Executive Vice President for Academic Affairs or Graduate Studies Administrator.
FOREWORD
Alcorn State University Office of Graduate Studies requires that all students comply with the
specifications given in this document in the publication of a thesis or non-thesis research project.
Graduate students, under faculty guidance, are expected to produce scholarly work either in the
form of a thesis or a scholarly research project.
The thesis (master or specialist) should document the student's research study and maintain a
degree of intensity.
The purpose of this manual is to assist the graduate student and the graduate thesis advisory
committee in each department with the instructions contained herein. This is the official
approved manual by the Graduate Division.
Formatting questions not addressed in these guidelines should be directed to the Graduate School
staff in the Walter Washington Administration Building, Suite 519 or by phone at
601.877.6122 or via email: [email protected] or in person.
The Graduate Studies
Thesis Advisory Committee
(Revised Spring 2018)
mailto:[email protected]
TABLE OF CONTENTS
Page
INTRODUCTION ............................................................................................................................ 3
SELECTION AND APPOINTMENT OF THESIS ADVISORY COMMITTEE ......................... 4
1. Early Topic Selection ......................................................................................................... 4
2. Selection of Thesis Chair ......................................................................................................... 4
3. Selection of Thesis Committee Members .......................................................................... 4
4. Appointment of Thesis Advisory Committee Form .......................................................... 4
5. Invitation to Prospective Committee Members ................................................................. 5
6. TAC Committee Selection ................................................................................................. 5
CHOICE OF SUBJECT .................................................................................................................... 5
PROPOSAL DEFENSE AND SUBMISSION OF PROPOSAL TO IRB ..................................... 5
PARTS OF THE MANUSCRIPT: PRELIMINARY PAGES ..................................................... 8
1. Title Page .
(a) Thrasymachus’ (the sophist’s) definition of Justice or Right o.docxAASTHA76
(a) Thrasymachus’ (the sophist’s) definition of Justice or Right or Right Doing/Living is “The Interest of the Stronger (Might makes Right).” How does Socrates refute this definition? (cite just
one
of his arguments) [cf:
The Republic
, 30-40, Unit 1 Lecture Video]
(b) According to Socrates, what is the true definition of Justice or Right? [cf:
The Republic
, 141-42, Unit 2 Lecture Video]
(c) And why therefore is the Just life far preferable to the Unjust life (142-43)?
(a) The Allegory of the CAVE (the main metaphor of western philosophy) is an illustration of the Divided LINE.
Characterize
the Two Worlds, and the move/ascent from one to the other (exiting the CAVE, crossing the Divided LINE)—which is alone the true meaning of Education and the only way to become Just, Right, and Immortal. [cf:
The Republic
, 227-232, Unit 3 Lecture Video]
(b) How do the philosophical Studies of
Arithmetic
(number) and
Dialectic
take you above the Divided Line and out of the changing sense-world of illusion (the CAVE) into Reality and make you use your Reason (pure thought) instead of your senses? [cf:
The Republic
, 235-37, 240-42, 250-55. Unit 4 Lecture Video (transcript)]
Give a summary of the
Proof of the Force
(Why there is the “Universe,” “Man,” “God,” “History,” etc)? Start with, “Can there be
nothing
?” [cf: TJH 78-95, Unit 2 Lecture Video]
NIETZSCHE is the crucial Jedi philosopher who provides the “bridge” between negative and positive Postmodernity by focusing on a certain “Problem” and the “
Solution
” to it.
(a) Discuss
2
of the following items (
1
pertaining to the Problem,
1
pertaining to the
.
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Preparation and mechanical characterization of epoxy based composite develope...eSAT Journals
Abstract Increasing concern about environment has made scientist and engineers very eager in their search for environmental friendly materials. So lot of research is going on today in the field of material science to develop newer materials. Natural fibers are getting much attention of researchers, engineers and scientists as reinforcement in the polymer matrix to develop natural fiber reinforced polymer composites. In the present work an attempt has been made to develop natural fibers reinforced polymer matrix composite. Advantages of using natural fibers are density reduction, cost savings and less weight to strength ratio. Composites with 10, 20 and 30 wt % coconut shell powder epoxy composites have been fabricated using Hand layup technique. Mechanical properties of these composites have been analyzed in detail. Keywords – Epoxy based Composites, Hand layup technique, Tensile strength, Flexural strength.
Analysis of the Flexure Behavior and Compressive Strength of Fly Ash Core San...IJERA Editor
In this paper, commercially available Fly Ash and Epoxy is used for the core material, woven glass fabric as reinforcing skin material, epoxy as matrix/adhesive materials used in this study for the construction of sandwich composite. Analysis is carried out on different proportions of epoxy and fly ash sandwiched composite material for determining the flexural strength and compressive strength, three different proportions of epoxy and fly ash used for the study. Those are 65%-35% (65% by weight fly ash and 35% by weight epoxy resin) composite material, 60%-40% and 55%-45% composite material. 60%-40% composite material specimen shows better results in the entire test carried out i.e. Flexure and Compression. The complete experimental results are discussed and presented in this paper.
STUDY ON THE INFLUENCE OF FIBER ORIENTATION ON PALF REINFORCED BISPHENOL COMP...IAEME Publication
The main advantage of a composite material over conventional material like a monolithic metal is the
combination of different properties which are seldom found in the conventional material. In recent years natural fibers
appear to be the outstanding materials which come as the viable and abundant substitute for the expensive and
nonrenewable synthetic fiber. Pineapple leaf fiber (PALF) is one of them that have also good potential as reinforcement
in thermoset composite. The objective of the present work is to investigate the effect of fiber orientation on the mechanical properties of PALF reinforced Bisphenol composite and explores the potential of using PALF as reinforcing
material.
Thermal conductivity Characterization of Bamboo fiber reinforced in Epoxy ResinIOSR Journals
Over a past few decades composites, plastics, ceramics have been the dominant engineering material. The areas of applications of composites materials have grown rapidly and have even found new markets. The current challenge is to make the durable in tough conditions to replace other materials and also to make them cost effective .This has resulted in development of many new techniques currently being used in the industry. While the use of composites it is clear choice in many applications but the selection of material will depend on the factor such as working life, lifetime requirement, complexity of product shape produced, saving the term cost. The availability of natural fiber is abundances and also they are very inexpensive when compared to other advanced manmade fibers. The primary advantage of natural fibers are low density, low cost, biodegradability, acceptable specific properties, less wear during extracting as well as manufacturing composites and wide varieties of natural fibers are locally available. The main focus of this investigation is to determine the thermal conductivity of bamboo fiber reinforced in epoxy resin composites. The test samples were prepared as per ASTM standards using simple hand-layup technique at different fiber weight fractions (10%, 20%30%, 40%50%, 60%). Thermal conductivity (K) of the composites material were determined experimentally and is validated by the results obtained by rule of mixture, E-S model and also by finite element modeling
MECHANICAL CHARACTERIZATION OF BIO-FIBRE AND GLASS FIBRE REINFORCED POLYESTER...ijceronline
Composites are versatile and convenient in diverse application such as automotive and aeronaut industry, constructional materials, civil and military applications and many more. Natural fiber composites are currently being used in mostly non-structural applications [1]. Natural fibers are being widely used to substitute artificial glass and carbon fibers in polymer composites. The aim of present work was to focus on the hybridization of natural fiber (jute) and synthetic fiber (E-glass) with polyester resin for applications in the aerospace industry [1]. The mechanical properties such as tensile, impact, flexural test and water absorption rate of hybrid glass/jute fiber reinforced polyester composites were determined. Laminates were fabricated by hand lay-up technique [2]. Then the mechanical properties of lamina prepared with different compositions of natural and synthetic fibers are compared. Total fiber weight fraction was maintained at 50%. Specimen preparation and testing was carried out as per ASTM standards [1], [2].
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Influence of Carbon & Glass Fiber Reinforcements on Flexural Strength of Epox...IJERA Editor
Hybrid composite materials are more attracted by the engineers because of their properties like stiffness and high specific strength which leads to the potential application in the area of aerospace, marine and automobile sectors. In the present investigation, the flexural strength and flexural modulus of carbon and glass fibers reinforced epoxy hybrid composites were studied. The vacuum bagging technique was adopted for the fabrication of polymer hybrid composite materials. The hardness, flexural strength and flexural modulus of the hybrid composites were determined as per ASTM standards. The hardness, flexural strength and flexural modulus were improved as the fiber reinforcement contents increased in the epoxy matrix material.
INVESTIGATION ON MECHANICAL PROPERTIES OF HEMP-E GLASS FIBER REINFORCED POLYM...IAEME Publication
Natural fiber composite is currently a leading module in the world of composites. It is due to many of its features such as freely available, easy processing, low cost, ability to replace usage of Glass fiber (Synthetic fiber), better strength properties and ecofriendly. They find useful applications in various fields from domestic to automotive sector as of now. Natural fibers with good content of lignocellulose, low density, and better elongation percentage are chosen for manufacturing of composites of above mentioned applications. Unidirectional & Continuous natural fiber composites are said to be anisotropic and having predominant mechanical properties.
Composites are engineered materials made from two or more constituents with different physical or chemical
properties, which remain separate and distinct within the finished structure. A fiber is a material, which is made into
a long filament with diameter generally in the order of 10 microns. The aspect ratio of length to diameter can be
ranging from thousands to infinity in continuous fibers. Increasing worldwide environmental awareness is
encouraging scientific research into the development of cheaper, more environmentally friendly and more
sustainable construction and packing materials. For environment concern on synthetic fiber (such as glass, carbon,
ceramic gibers etc) natural fibers (such as flax, hemp, jute, kenai) etc are widely used. Industrial hemp fiber is one
of the strongest of the natural fibers available and possesses benefits such as low cost and low production energy
requirements. The primary objective of this research is to fabricate the natural fiber composites with suitable
processing/manufacturing methods and to examine the mechanical properties when subjected to Tension, Bending
and to compare & contrast the results with the available literature. In this research work, hemp fiber reinforced
Epoxy matrix composites have been developed by hand layup method with varying process parameters, such as
coupling agent(with and without compatibilizers) and different fiber percentages (10%,20% and 30% by weight).
The developed composites were then characterized by tensile test and flexural testing. Results show that the tensile
strength and flexural properties increases with the increase in fiber percentage. However after a certain percentage
the tensile strength decreases again. Compared to untreated hemp fiber, no significant changes in the tensile strength
have been observed for treated hemp fiber reinforcement. The flexural strength / modulus of the composite were
higher compared to pure epoxy for all filler/fiber loadings.
Fabrication, experimental investigation of jute fiber reinforced epoxy compos...Adib Bin Rashid
A special type of jute fiber woven mat was introduced by a hand loom. Epoxy jute
fiber composites were fabricated using the woven fiber mat. A series of jute-hybrid epoxy composites based on the arrangement of the direction of jute fibers, and additional material were introduced to ensure the elevated mechanical properties of the composites. Improved
mechanical properties were found in some cases of hybrid epoxy composites. It is discussed that the mechanical behavior is related to the fiber orientation, types of additional materials used in hybrid materials. The purpose of this study is to propose a simple technical method to prepare woven jute fiber mat by hand loom, and to produce epoxy jute fiber, hybrid composite materials to exhibit the elevated mechanical properties.
(APA 6th Edition Formatting and Style Guide)
Office of Graduate Studies
Alcorn State University
Engaging Possibilities, Pursuing Excellence
REVISED May 23, 2018
THESIS MANUAL
Graduates
2
COPYRIGHT PRIVILEGES
BELONG TO
OFFICE OF GRADUATE STUDIES
ALCORN STATE UNIVERSITY, LORMAN, MS
Reproduction for distribution of this THESIS MANUAL requires the written permission of the
Provost and Executive Vice President for Academic Affairs or Graduate Studies Administrator.
FOREWORD
Alcorn State University Office of Graduate Studies requires that all students comply with the
specifications given in this document in the publication of a thesis or non-thesis research project.
Graduate students, under faculty guidance, are expected to produce scholarly work either in the
form of a thesis or a scholarly research project.
The thesis (master or specialist) should document the student's research study and maintain a
degree of intensity.
The purpose of this manual is to assist the graduate student and the graduate thesis advisory
committee in each department with the instructions contained herein. This is the official
approved manual by the Graduate Division.
Formatting questions not addressed in these guidelines should be directed to the Graduate School
staff in the Walter Washington Administration Building, Suite 519 or by phone at
601.877.6122 or via email: [email protected] or in person.
The Graduate Studies
Thesis Advisory Committee
(Revised Spring 2018)
mailto:[email protected]
TABLE OF CONTENTS
Page
INTRODUCTION ............................................................................................................................ 3
SELECTION AND APPOINTMENT OF THESIS ADVISORY COMMITTEE ......................... 4
1. Early Topic Selection ......................................................................................................... 4
2. Selection of Thesis Chair ......................................................................................................... 4
3. Selection of Thesis Committee Members .......................................................................... 4
4. Appointment of Thesis Advisory Committee Form .......................................................... 4
5. Invitation to Prospective Committee Members ................................................................. 5
6. TAC Committee Selection ................................................................................................. 5
CHOICE OF SUBJECT .................................................................................................................... 5
PROPOSAL DEFENSE AND SUBMISSION OF PROPOSAL TO IRB ..................................... 5
PARTS OF THE MANUSCRIPT: PRELIMINARY PAGES ..................................................... 8
1. Title Page .
(a) Thrasymachus’ (the sophist’s) definition of Justice or Right o.docxAASTHA76
(a) Thrasymachus’ (the sophist’s) definition of Justice or Right or Right Doing/Living is “The Interest of the Stronger (Might makes Right).” How does Socrates refute this definition? (cite just
one
of his arguments) [cf:
The Republic
, 30-40, Unit 1 Lecture Video]
(b) According to Socrates, what is the true definition of Justice or Right? [cf:
The Republic
, 141-42, Unit 2 Lecture Video]
(c) And why therefore is the Just life far preferable to the Unjust life (142-43)?
(a) The Allegory of the CAVE (the main metaphor of western philosophy) is an illustration of the Divided LINE.
Characterize
the Two Worlds, and the move/ascent from one to the other (exiting the CAVE, crossing the Divided LINE)—which is alone the true meaning of Education and the only way to become Just, Right, and Immortal. [cf:
The Republic
, 227-232, Unit 3 Lecture Video]
(b) How do the philosophical Studies of
Arithmetic
(number) and
Dialectic
take you above the Divided Line and out of the changing sense-world of illusion (the CAVE) into Reality and make you use your Reason (pure thought) instead of your senses? [cf:
The Republic
, 235-37, 240-42, 250-55. Unit 4 Lecture Video (transcript)]
Give a summary of the
Proof of the Force
(Why there is the “Universe,” “Man,” “God,” “History,” etc)? Start with, “Can there be
nothing
?” [cf: TJH 78-95, Unit 2 Lecture Video]
NIETZSCHE is the crucial Jedi philosopher who provides the “bridge” between negative and positive Postmodernity by focusing on a certain “Problem” and the “
Solution
” to it.
(a) Discuss
2
of the following items (
1
pertaining to the Problem,
1
pertaining to the
.
(Glossary of Telemedicine and eHealth)· Teleconsultation Cons.docxAASTHA76
(Glossary of Telemedicine and eHealth)
· Teleconsultation: Consultation between a provider and specialist at distance using either store and forward telemedicine or real time videoconferencing.
· Telehealth and Telemedicine: Telemedicine is the use of medical information exchanged from one site to another via electronic communications to improve patients' health status. Closely associated with telemedicine is the term "telehealth," which is often used to encompass a broader definition of remote healthcare that does not always involve clinical services. Videoconferencing, transmission of still images, e-health including patient portals, remote monitoring of vital signs, continuing medical education and nursing call centers are all considered part of telemedicine and telehealth. Telemedicine is not a separate medical specialty. Products and services related to telemedicine are often part of a larger investment by health care institutions in either information technology or the delivery of clinical care. Even in the reimbursement fee structure, there is usually no distinction made between services provided on site and those provided through telemedicine and often no separate coding required for billing of remote services. Telemedicine encompasses different types of programs and services provided for the patient. Each component involves different providers and consumers.
· TeleICU: TeleICU is a collaborative, interprofessional model focusing on the care of critically ill patients using telehealth technologies.
· Telemonitoring: The process of using audio, video, and other telecommunications and electronic information processing technologies to monitor the health status of a patient from a distance.
· Telemonitoring: The process of using audio, video, and other telecommunications and electronic information processing technologies to monitor the health status of a patient from a distance.
· Clinical Decision Support System (CCDS): Systems (usually electronically based and interactive) that provide clinicians, staff, patients, and other individuals with knowledge and person-specific information, intelligently filtered and presented at appropriate times, to enhance health and health care. (http://healthit.ahrq.gov/images/jun09cdsreview/09_0069_ef.html)
· e-Prescribing: The electronic generation, transmission and filling of a medical prescription, as opposed to traditional paper and faxed prescriptions. E-prescribing allows for qualified healthcare personnel to transmit a new prescription or renewal authorization to a community or mail-order pharmacy.
· Home Health Care and Remote Monitoring Systems: Care provided to individuals and families in their place of residence for promoting, maintaining, or restoring health or for minimizing the effects of disability and illness, including terminal illness. In the Medicare Current Beneficiary Survey and Medicare claims and enrollment data, home health care refers to home visits by professionals including nu.
(Assmt 1; Week 3 paper) Using ecree Doing the paper and s.docxAASTHA76
(Assmt 1; Week 3 paper): Using ecree Doing the paper and submitting it (two pages here)
Have this sheet handy as well as the sheet called FORMAT SAMPLE PAPER for Assignment 1.
1. Go to the Week 3 unit and find the blue link ASSIGNMENT 1: DEALING WITH DIVERSITY…. Click on it.
2. You will see instructions on the screen and at the top “Assignment 1: ecree”. Click on that to enter ecree.
3. You will see some summary of the assignment instructions at the top of the screen—scroll down to see the three long, blank, rectangular boxes. You will be typing into those. Remember—do not worry about a title page or double spacing. Start composing your paragraphs. It will start as a rough draft.
4. As you start typing your introduction—notice on the right that comments start developing and also video links. Also on the right you will it say “Saved a Few seconds ago”. It is saving as you go. At first the comments are red (unfavorable). The more you do, usually the more green (favorable) comments start to appear. You can also keep revising.
5. When you hit the enter key it takes you to the next paragraph box—and sometimes it creates a new paragraph box for you.
6. Doing your Sources list in ecree—Your sources do have to be listed at the end. The FORMAT SAMPLE paper illustrates what they might look like. But, putting them in ecree gracefully can be a challenge.
a. Perhaps the best way is this: Have the last regular paragraph of your essay (Part 4) be in the box labeled “Conclusion”. Once that paragraph is written—in whole or in part, do this: Click on the word “Conclusion” to form a following paragraph box marked by three dots. Keep doing that and put each source in its own “three-dot” box. In other words, after your Conclusion paragraph—the heading “Sources” gets its own paragraph box at the end, followed by separate paragraph boxes for each source entry.
b. If the approach labeled “a” above is not working out, don’t worry about the external labels of those last paragraph boxes---just be sure to have a concluding paragraph (your Part 4) followed by paragraphs for the Sources header and each source entry. In grading, I will be able to figure it out. I will be lenient on how you organize that last part, as long as you have that last paragraph and a clear Sources list.
------------------------------------
UPLOAD OPTION: You can type your paper or a good rough draft of it into MS-Word as a file. Have it organized and laid out like the FORMAT SAMPLE paper. Then Upload it to ecree. Once you upload, take a little time and edit what uploaded so that it looks like what you intended and fits the 4-part organization of the assignment.
-----------------------
7. Click “Submit” on lower right only when absolutely ready. Once you submit, it will get graded.
Have fun! (see next page for a few notes and comments on ecree)
---------.
(Image retrieved at httpswww.google.comsearchhl=en&biw=122.docxAASTHA76
(Image retrieved at https://www.google.com/search?hl=en&biw=1229&bih=568&tbm=isch&sa=1&ei=fmYIW9W3G6jH5gLn7IHYAQ&q=analysis&oq=analysis&gs_l=img.3..0i67k1l2j0l5j0i67k1l2j0.967865.968569.0.969181.7.4.0.0.0.0.457.682.1j1j4-1.3.0....0...1c.1.64.img..5.2.622...0i7i30k1.0.rL9KcsvXM1U#imgrc=LU1vXlB6e2doDM: / )
ESOL 052 (Essay #__)
Steps:
1. Discuss the readings, videos, and photographs in the Truth and Lies module on Bb.
2. Select a significant/controversial photograph to analyze. (The photograph does not have to be from Bb.)
3. Choose one of the following essay questions:
a. What truth does this photograph reveal?
b. What lie does this photograph promote?
c. Why/How did people deliberately misuse this photograph and distort its true meaning?
d. Why was this photograph misinterpreted by so many people?
e. Why do so many people have different reactions to this photograph?
f. ___________________________________________________________________________?
(Students may create their own visual analysis essay question as long as it is pre-approved by the instructor.)
4. Use the OPTIC chart to brainstorm and take notes on your photograph.
5. Use a pre-writing strategy (outline, graphic organizer, etc.) to organize your ideas.
6. Using correct MLA format, write a 3-5 page essay.
7. Type a Works Cited page. (Use citationmachine.net, easybib.com, etc. to format your info.)
8. Peer and self-edit during the writing process (Bb Wiki, in/outside class).
9. Get feedback from your peers and an instructor during the writing process.
(Note: Students who visit the Writing Center and show me proof get 2 additional days to work on the assignment.)
10. Proofread/edit/revise during the writing process.
11. Put your pre-writing, essay, and Works Cited page in 1 Word document and upload it on Bb by midnight on ______. (If a student submits an essay without pre-writing or without a Works Cited page, he/she will receive a zero. If a student submits an assignment late, he/she will receive a zero. If a student plagiarizes, he/she will receive a zero.)
Purpose: Students will be able to use their reading, writing, critical thinking, and research skills to conduct a visual analysis that explores the theme of Truth and Lies.
Tone: The tone of this assignment should be formal and academic.
Language: The diction and syntax of this assignment should be formal and academic. Students should not use second person pronouns (you/your), contractions, abbreviations, slang, or any type of casual language. Students should refer to the diction and syntax guidelines in the writing packet.
Audience: The audience of this assignment is the student’s peers and instructor.
Format: MLA style (double spaced, 1 in. margins, Times New Roman 12 font, pagination, heading, title, tab for each paragraph, in-text citations, Works Cited page, hanging indents, etc.)
Requirements:
In order for a student to earn a minimum passing grade of 70% on this assignment, h.
(Dis) Placing Culture and Cultural Space Chapter 4.docxAASTHA76
(Dis) Placing Culture and Cultural Space
Chapter 4
+
Chapter Objectives
Describe the relationships among culture, place, cultural space, and identity in the context of globalization.
Explain how people use communicative practices to construct, maintain, negotiate, and hybridize cultural spaces.
Explain how cultures are simultaneously placed and displaced in the global context leading to segregated, contested and hybrid cultural spaces.
Describe the practice of bifocal vision to highlight the linkages between “here” and “there” as well as the connections between present and past.
+
Introduction
Explore the cultural and intercultural communication dimensions of place, space and location. We will examine:
The dynamic process of placing and displacing cultural space in the context of globalization.
How people use communicative practices to construct, maintain, negotiate, and hybridize cultural spaces
How segregated, contested, and hybrid cultural spaces are both shaped by the legacy of colonialism and the context of globalization.
How Hip hop culture illustrates the cultural and intercultural dimensions of place, space, and location in the context of globalization
+
Placing Culture and Cultural Space
Culture, by definition, is rooted in place with a reciprocal relationship between people and place
Culture:
“Place tilled” in Middle English
Colere : “to inhabit, care for, till, worship” in Latin
In the context of globalization, what is the relationship between culture and place?
Culture is both placed and displaced
+
Cultural Space
The communicative practices that construct meanings in, through and about particular places
Cultural space shapes verbal and nonverbal communicative practices
i.e. Classrooms, dance club, library.
Cultural spaces are constructed through the communicative practices developed and lived by people in particular places
Communicative practices include:
The languages, accents, slang, dress, artifacts, architectural design, the behaviors and patterns of interaction, the stories, the discourses and histories
How is the cultural space of your home, neighborhood, city, and state constructed through communicative practices?
+
Place, Cultural Space and Identity
Place, Culture, Identity and Difference
What’s the relationship between place and identity?
Avowed identity:
The way we see, label and make meaning about ourselves and
Ascribed identity:
The way others view, name and describe us and our group
Examples of how avowed and ascribed identities may conflict?
How is place related to standpoint and power?
Locations of enunciation:
Sites or positions from which to speak.
A platform from which to voice a perspective and be heard and/or silenced.
+
Displacing Culture and Cultural Space
(Dis) placed culture and cultural space:
A notion that captures the complex, contradictory and contested nature of cultural space and the relationship between culture and place that has emerged in the context o.
(1) Define the time value of money. Do you believe that the ave.docxAASTHA76
(1) Define the time value of money. Do you believe that the average person considers the time value of money when they make investment decisions? Please explain.
(2) Distinguish between ordinary annuities and annuities due. Also, distinguish between the future value of an annuity and the present value of an annuity.
.
(chapter taken from Learning Power)From Social Class and t.docxAASTHA76
(chapter taken from Learning Power)
From Social Class and the Hidden Curriculum of Work
JEAN ANYON
It's no surprise that schools in wealthy communities are better than those in poor communities, or that they better prepare their students for
desirable jobs. It may be shocking, however, to learn how vast the differences in schools are - not so much in resources as in teaching methods
and philosophies of education. Jean Anyon observed five elementary schools over the course of a full school year and concluded that fifth-
graders of different economic backgrounds are already being prepared to occupy particular rungs on the social ladder. In a sense, some whole
schools are on the vocational education track, while others are geared to produce future doctors, lawyers, and business leaders. Anyon's main
audience is professional educators, so you may find her style and vocabulary challenging, but, once you've read her descriptions of specific
classroom activities, the more analytic parts of the essay should prove easier to understand. Anyon is chairperson of the Department of
Education at Rutgers University, Newark; This essay first appeared in Journal of Education in 1980.
Scholars in political economy and the sociology of knowledge have recently argued that public schools in complex industrial societies like our
own make available different types of educational experience and curriculum knowledge to students in different social classes. Bowles and
Gintis1 for example, have argued that students in different social-class backgrounds are rewarded for classroom behaviors that correspond to
personality traits allegedly rewarded in the different occupational strata--the working classes for docility and obedience, the managerial classes
for initiative and personal assertiveness. Basil Bernstein, Pierre Bourdieu, and Michael W. Apple focusing on school knowledge, have argued
that knowledge and skills leading to social power and regard (medical, legal, managerial) are made available to the advantaged social groups but
are withheld from the working classes to whom a more "practical" curriculum is offered (manual skills, clerical knowledge). While there has
been considerable argumentation of these points regarding education in England, France, and North America, there has been little or no attempt
to investigate these ideas empirically in elementary or secondary schools and classrooms in this country.3
This article offers tentative empirical support (and qualification) of the above arguments by providing illustrative examples of differences in
student work in classrooms in contrasting social class communities. The examples were gathered as part of an ethnographical4 study of
curricular, pedagogical, and pupil evaluation practices in five elementary schools. The article attempts a theoretical contribution as well and
assesses student work in the light of a theoretical approach to social-class analysis.. . It will be suggested that there is a "hidden.
(Accessible at httpswww.hatchforgood.orgexplore102nonpro.docxAASTHA76
(Accessible at https://www.hatchforgood.org/explore/102/nonprofit-photography-ethics-and-approaches)
Nonprofit Photography: Ethics
and Approaches
Best practices and tips on ethics and approaches in
humanitarian photography for social impact.
The first moon landing. The Vietnamese ‘napalm girl’, running naked and in agony. The World
Trade Centers falling.
As we know, photography carries the power to inspire, educate, horrify and compel its viewers to
take action. Images evoke strong and often public emotions, as people frequently formulate their
opinions, judgments and behaviors in response to visual stimuli. Because of this, photography
can wield substantial control over public perception and discourse.
Moreover, photography in our digital age permits us to deliver complex information about
remote conditions which can be rapidly distributed and effortlessly processed by the viewer.
Recently, we’ve witnessed the profound impact of photography coupled with social media:
together, they have fueled political movements and brought down a corrupt government.
Photography can - and has - changed the course of history.
Ethical Considerations
Those who commission and create photography of marginalized populations to further an
organizations’ mission possess a tremendous responsibility. Careful ethical consideration should
be given to all aspects of the photography supply chain: its planning, creation, and distribution.
When planning a photography campaign, it is important to examine the motives for creating
particular images and their potential impact. Not only must a faithful, comprehensive visual
depiction of the subjects be created to avoid causing misconception, but more importantly, the
subjects’ dignity must be preserved. Words and images that elicit an emotional response by their
sheer shock value (e.g. starving, skeletal children covered in flies) are harmful because they
exploit the subjects’ condition in order to generate sympathy for increasing charitable donations
or support for a given cause. In addition to violating privacy and human rights, this so-called
'poverty porn’ is harmful to those it is trying to aid because it evokes the idea that the
marginalized are helpless and incapable of helping themselves, thereby cultivating a culture of
paternalism. Poverty porn is also detrimental because it is degrading, dishonoring and robs
people of their dignity. While it is important to illustrate the challenges of a population, one must
always strive to tell stories in a way that honors the subjects’ circumstances, and (ideally)
illustrates hope for their plight.
Legal issues
Legal issues are more clear cut when images are created or used in stable countries where legal
precedent for photography use has been established. Image use and creation becomes far more
murky and problematic in countries in which law and order is vague or even nonexistent.
Even though images created for no.
(a) The current ratio of a company is 61 and its acid-test ratio .docxAASTHA76
(a) The current ratio of a company is 6:1 and its acid-test ratio is 1:1. If the inventories and prepaid items amount to $445,500, what is the amount of current liabilities?
Current Liabilities
$
89100
(b) A company had an average inventory last year of $113,000 and its inventory turnover was 6. If sales volume and unit cost remain the same this year as last and inventory turnover is 7 this year, what will average inventory have to be during the current year? (Round answer to 0 decimal places, e.g. 125.)
Average Inventory
$
96857
(c) A company has current assets of $88,800 (of which $35,960 is inventory and prepaid items) and current liabilities of $35,960. What is the current ratio? What is the acid-test ratio? If the company borrows $12,970 cash from a bank on a 120-day loan, what will its current ratio be? What will the acid-test ratio be? (Round answers to 2 decimal places, e.g. 2.50.)
Current Ratio
2.47
:1
Acid Test Ratio
:1
New Current Ratio
:1
New Acid Test Ratio
:1
(d) A company has current assets of $586,700 and current liabilities of $200,100. The board of directors declares a cash dividend of $173,700. What is the current ratio after the declaration but before payment? What is the current ratio after the payment of the dividend? (Round answers to 2 decimal places, e.g. 2.50.)
Current ratio after the declaration but before payment
:1
Current ratio after the payment of the dividend
:1
The following data is given:
December 31,
2015
2014
Cash
$66,000
$52,000
Accounts receivable (net)
90,000
60,000
Inventories
90,000
105,000
Plant assets (net)
380,500
320,000
Accounts payable
54,500
41,500
Salaries and wages payable
11,500
5,000
Bonds payable
70,500
70,000
8% Preferred stock, $40 par
100,000
100,000
Common stock, $10 par
120,000
90,000
Paid-in capital in excess of par
80,000
70,000
Retained earnings
190,000
160,500
Net credit sales
930,000
Cost of goods sold
735,000
Net income
81,000
Compute the following ratios: (Round answers to 2 decimal places e.g. 15.25.)
(a)
Acid-test ratio at 12/31/15
: 1
(b)
Accounts receivable turnover in 2015
times
(c)
Inventory turnover in 2015
times
(d)
Profit margin on sales in 2015
%
(e)
Return on common stock equity in 2015
%
(f)
Book value per share of common stock at 12/31/15
$
Exercise 24-4
As loan analyst for Utrillo Bank, you have been presented the following information.
Toulouse Co.
Lautrec Co.
Assets
Cash
$113,900
$311,200
Receivables
227,200
302,700
Inventories
571,200
510,700
Total current assets
912,300
1,124,600
Other assets
506,000
619,800
Total assets
$1,418,300
$1,744,400
Liabilities and Stockholders’ Equity
Current liabilities
$291,300
$350,400
Long-term liabilities
390,800
506,000
Capital stock and retained earnings
736,200
888,000
Total liabilities and stockholders’ equity
$1.
(1) How does quantum cryptography eliminate the problem of eaves.docxAASTHA76
(1) How does quantum cryptography eliminate the problem of eavesdropping in traditional cryptography?
(2) What are the limitations or problems associated with quantum cryptography?
(3) What features or activities will affect both the current and future developments of cryptography?
Use of proper APA formatting and citations. If supporting evidence from outside resources is used those must be properly cited.
References
.
#transformation
10
Event
Trends
for 2019
10 Event Trends for 2019
C O P Y R I G H T
All rights reserved. No part of this report may be
reproduced or transmitted in any form or by any
means whatsoever (including presentations, short
summaries, blog posts, printed magazines, use
of images in social media posts) without express
written permission from the author, except in the
case of brief quotations (50 words maximum and
for a maximum of 2 quotations) embodied in critical
articles and reviews, and with clear reference to
the original source, including a link to the original
source at https://www.eventmanagerblog.com/10-
event-trends/. Please refer all pertinent questions
to the publisher.
page 2
https://www.eventmanagerblog.com/10-event-trends/
https://www.eventmanagerblog.com/10-event-trends/
10 Event Trends for 2019
CONTENTS
INTRODUCTION page 5
TRANSFORMATION 8
10. PASSIVE ENGAGEMENT 10
9. CONTENT DESIGN 13
8. SEATING MATTERS 16
7. JOMO - THE JOY OF MISSING OUT 19
6. BETTER SAFE THAN SORRY 21
5. CAT SPONSORSHIP 23
4. SLOW TICKETING 25
3. READY TO BLOCKCHAIN 27
2. MARKETING BUDGETS SHIFTING MORE TO EVENTS 28
1. MORE THAN PLANNERS 30
ABOUT THE AUTHOR 31
CMP CREDITS 32
CREDITS AND THANKS 32
DISCLAIMER 32
page 3
INTERACTIVITY
AT THE HEART OF YOUR MEETINGS
Liven up your presentations!
EVENIUM
ConnexMe
San Francisco/Paris [email protected]
AD
https://eventmb.com/2PvIw1f
10 Event Trends for 2019
I am very glad to welcome you to the 8th edition of our annual
event trends. This is going to be a different one.
One element that made our event trends stand out from
the thousands of reports and articles on the topic is that we
don’t care about pleasing companies, pundits, suppliers, star
planners and the likes. Our only focus is you, the reader, to
help you navigate through very uncertain times.
This is why I decided to bring back this report, by far the most
popular in the industry, to its roots. 10 trends that will actually
materialize between now and November 2019, when we will
publish edition number nine.
I feel you have a lot going on, with your events I mean.
F&B, room blocks, sponsorship, marketing security, technology.
I think I failed you in previous editions. I think I gave you too
much. This report will be the most concise and strategic piece
of content you will need for next year.
If you don’t read anything else this year, it’s fine. As long as you
read the next few words.
INTRODUCTION
INTRODUCTION -
Julius Solaris
EventMB Editor
page 5
https://www.eventmanagerblog.com
10 Event Trends for 2019
How did I come up with these trends?
~ As part of this report, we reviewed 350 events. Some of the most successful
worldwide.
~ Last year we started a community with a year-long trend watch. That helped
us to constantly research new things happening in the industry.
~ We have reviewed north of 300 event technology solutions for our repor.
$10 now and $10 when complete Use resources from the required .docxAASTHA76
$10 now and $10 when complete
Use resources from the required readings or the GCU Library to create a 10‐15 slide digital presentation to be shown to your colleagues informing them of specific cultural norms and sociocultural influences affecting student learning at your school.
Choose a culture to research. State the country or countries of origin of your chosen culture and your reason for selecting it.
Include sociocultural influences on learning such as:
Religion
Dress
Cultural Norms
Food
Socialization
Gender Differences
Home Discipline
Education
Native Language
Include presenter’s notes, a title slide, in‐text citations, and a reference slide that contains three to five sources from the required readings or the GCU Library.
.
#include <string.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <stdio.h>
#include <unistd.h>
#include <string.h>
// Function: void parse(char *line, char **argv)
// Purpose : This function takes in a null terminated string pointed to by
// <line>. It also takes in an array of pointers to char <argv>.
// When the function returns, the string pointed to by the
// pointer <line> has ALL of its whitespace characters (space,
// tab, and newline) turned into null characters ('\0'). The
// array of pointers to chars will be modified so that the zeroth
// slot will point to the first non-null character in the string
// pointed to by <line>, the oneth slot will point to the second
// non-null character in the string pointed to by <line>, and so
// on. In other words, each subsequent pointer in argv will point
// to each subsequent "token" (characters separated by white space)
// IN the block of memory stored at the pointer <line>. Since all
// the white space is replaced by '\0', every one of these "tokens"
// pointed to by subsequent entires of argv will be a valid string
// The "last" entry in the argv array will be set to NULL. This
// will mark the end of the tokens in the string.
//
void parse(char *line, char **argv)
{
// We will assume that the input string is NULL terminated. If it
// is not, this code WILL break. The rewriting of whitespace characters
// and the updating of pointers in argv are interleaved. Basically
// we do a while loop that will go until we run out of characters in
// the string (the outer while loop that goes until '\0'). Inside
// that loop, we interleave between rewriting white space (space, tab,
// and newline) with nulls ('\0') AND just skipping over non-whitespace.
// Note that whenever we encounter a non-whitespace character, we record
// that address in the array of address at argv and increment it. When
// we run out of tokens in the string, we make the last entry in the array
// at argv NULL. This marks the end of pointers to tokens. Easy, right?
while (*line != '\0') // outer loop. keep going until the whole string is read
{ // keep moving forward the pointer into the input string until
// we encounter a non-whitespace character. While we're at it,
// turn all those whitespace characters we're seeing into null chars.
while (*line == ' ' || *line == '\t' || *line == '\n' || *line == '\r')
{ *line = '\0';
line++;
}
// If I got this far, I MUST be looking at a non-whitespace character,
// or, the beginning of a token. So, let's record the address of this
// beginning of token to the address I'm pointing at now. (Put it in *argv)
.
$ stated in thousands)Net Assets, Controlling Interest.docxAASTHA76
$ stated in thousands)
Net Assets, Controlling Interest
–
–
Net Assets, Noncontrolling Interest
AUDIT COMMITTEE
of the
Executive Board of the Boy Scouts of America
Francis R. McAllister, Chairman
David Biegler Ronald K. Migita
Dennis H. Chookaszian David Moody
Report of Independent Auditors
To the Executive Board of the National Council of the Boy Scouts of America
We have audited the accompanying consolidated financial statements of the National Council of the Boy Scouts
of America and its affiliates (the National Council), which comprise the consolidated statement of financial position
as of December 31, 2016, and the related consolidated statements of revenues, expenses, and other changes in net
assets, of functional expenses and of cash flows for the year then ended.
Management’s Responsibility for the Consolidated Financial Statements
Management is responsible for the preparation and fair presentation of the consolidated financial statements
in accordance with accounting principles generally accepted in the United States of America; this includes the
design, implementation and maintenance of internal control relevant to the preparation and fair presentation of
consolidated financial statements that are free from material misstatement, whether due to fraud or error.
Auditors’ Responsibility
Our responsibility is to express an opinion on the consolidated financial statements based on our audit. We
conducted our audit in accordance with auditing standards generally accepted in the United States of America.
Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the
consolidated financial statements are free from material misstatement.
An audit involves performing procedures to obtain audit evidence about the amounts and disclosures in the
consolidated financial statements. The procedures selected depend on our judgment, including the assessment of
the risks of material misstatement of the consolidated financial statements, whether due to fraud or error. In making
those risk assessments, we consider internal control relevant to the National Council’s preparation and fair
presentation of the consolidated financial statements in order to design audit procedures that are appropriate in the
circumstances, but not for the purpose of expressing an opinion on the effectiveness of the National Council’s
internal control. Accordingly, we express no such opinion. An audit also includes evaluating the appropriateness of
accounting policies used and the reasonableness of significant accounting estimates made by management, as well as
evaluating the overall presentation of the consolidated financial sta.
#include <stdio.h>
#include <stdlib.h>
#include <pthread.h>
#include <time.h>
#include <unistd.h>
// Change the constant below to change the number of philosophers
// coming to lunch...
// This is a known GOOD solution based on the Arbitrator
// solution
#define PHILOSOPHER_COUNT 20
// Each philosopher is represented by one thread. Each thread independenly
// runs the same "think/start eating/finish eating" program.
pthread_t philosopher[PHILOSOPHER_COUNT];
// Each chopstick gets one mutex. If there are N philosophers, there are
// N chopsticks. That's the whole problem. There's not enough chopsticks
// for all of them to be eating at the same time. If they all cooperate,
// everyone can eat. If they don't... or don't know how.... well....
// philosophers are going to starve.
pthread_mutex_t chopstick[PHILOSOPHER_COUNT];
// The arbitrator solution adds a "waiter" that ensures that only pairs of
// chopsticks are grabbed. Here is the mutex for the waiter ;)
pthread_mutex_t waiter;
void *philosopher_program(int philosopher_number)
{ // In this version of the "philosopher program", the philosopher
// will think and eat forever.
while (1)
{ // Philosophers always think before they eat. They need to
// build up a bit of hunger....
//printf ("Philosopher %d is thinking\n", philosopher_number);
usleep(1);
// That was a lot of thinking.... now hungry... this
// philosopher (who knows his own number) grabs the chopsticks
// to her/his right and left. The chopstick to the left of
// philosopher N is chopstick N. The chopstick to the right
// of philosopher N is chopstick N+1
//printf ("Philosopher %d wants chopsticks\n",philosopher_number);
pthread_mutex_lock(&waiter);
pthread_mutex_lock(&chopstick[philosopher_number]);
pthread_mutex_lock(&chopstick[(philosopher_number+1)%PHILOSOPHER_COUNT]);
pthread_mutex_unlock(&waiter);
// Hurray, if I got this far I'm eating
printf ("Philosopher %d is eating\n",philosopher_number);
//usleep(1); // I spend twice as much time eating as thinking...
// typical....
// I'm done eating. Now put the chopsticks back on the table
//printf ("Philosopher %d finished eating\n",philosopher_number);
pthread_mutex_unlock(&chopstick[philosopher_number]);
pthread_mutex_unlock(&chopstick[(philosopher_number+1)%PHILOSOPHER_COUNT]);
//printf("Philosopher %d has placed chopsticks on the table\n", philosopher_number);
}
return(NULL);
}
int main()
{ int i;
srand(time(NULL));
for(i=0;i<PHILOSOPHER_COUNT;i++)
pthread_mutex_init(&chopstick[i],NULL);
pthread_mutex_init(&waiter,NULL);
for(i=0;i<PH.
#Assessment BriefDiploma of Business Eco.docxAASTHA76
#
Assessment BriefDiploma of Business Economics for Business
Credit points : 6 Prerequisites : None Co-requisites :
Subject Coordinator : Harriet Scott
Deadline : Sunday at the end of week 10 (Turnitin via CANVAS submission). Reflection due week 11 in tutorials.
ASSESSMENT TASK #3: FINAL CASE STUDY REPORT 25%
TASK DESCRIPTION
This assessment is a formal business report on a case study. Case studies will be assigned to students in the Academic and Business Communication subject. Readings on the case study are available on Canvas, in the Economics for Business subject. Students will also write a reflection on learning in tutorial classes in week 11.
LEARNING OUTCOMES
· Demonstrates understanding of microeconomic and macroeconomic concepts
· Applies economic concepts to contemporary issues and events
· Evaluates possible solutions for contemporary economic and business problems
· Communicates economic information in a business report format
INSEARCH CRICOS provider code: 00859D I UTS CRICOS provider code: 00099F INSEARCH Limited is a controlled entity of the University of Technology, Sydney (UTS), a registered non-self accrediting higher education institution and a pathway provider to UTS.
1. Refer to the case study you are working on for your presentation in Academic and Business Communication. Read the news stories for your case study, found on Canvas.
2. Individually, write a business report that includes the following information:
· Description of the main issue/problem and causes
· Description of the impact on stakeholders
· Analysis of economic concepts relevant to the case study (3-5 concepts)
· Recommendations for alternate solutions to the issue/problem
3. In your week 11 tutorial, write your responses to the reflection questions provided by your tutor, describing your learning experience in this assessment.
Other Requirements Format: Business Report
· Use the Business Report format as taught in BABC001 (refer to CANVAS Help for more information)
· Write TEEL paragraphs (refer to CANVAS Help for more information)
· All work submitted must be written in your own words, using paraphrasing techniques taught in BABC001
· Check Canvas — BECO — Assessments — Final Report page and ‘Writing a report' flyer for more information
Report Presentation: You need to include:
· Cover page as taught in BABC001
· Table of contents - list headings, subheadings and page numbers
· Reference list - all paraphrased/summarised/quoted evidence should include citations; all citations should be detailed in the Reference List
Please ensure your assignment is presented professionally. Suggested structure:
· Cover page
· Table of contents (bold, font size 18)
· Executive summary (bold, font size 18)
· 1.0 Introduction (bold, font size 16)
· 2.0 Main issue (bold, font size 16)
o 2.1 Causes (italics, font size 14)
· 3.0 Stakeholders (bold, font size 16)
o 3.1 Stakeholder 1 (italics, font size 14) o 3.2 Stakeholder 2 (italics, font size 14) o 3.3 Stakeholde.
#include <stdio.h>
#include <stdint.h>
#include <stdbool.h>
// Prototype of FOUR functions, each for a STATE.
// The func in State 1 performs addition of "unsigned numbers" x0 and x1.
int s1_add_uintN(int x0, int x1, bool *c_flg);
// The func in State 2 performs addition of "signed numbers" x0 and x1.
int s2_add_intN(int x0, int x1, bool *v_flg);
// The func in State 3 performs subtraction of "unsigned numbers" x0 and x1.
int s3_sub_uintN(int x0, int x1, bool *c_flg);
// The func in State 3 performs subtraction of "signed numbers" x0 and x1.
int s4_sub_intN(int x0, int x1, bool *v_flg);
// We define the number of bits and the related limits of unsigned and
// and signed numbers.
#define N 5 // number of bits
#define MIN_U 0 // minimum value of unsigned N-bit number
#define MAX_U ((1 << N) - 1) // maximum value of unsigned N-bit number
#define MIN_I (-(1 << (N-1)) ) // minimum value of signed N-bit number
#define MAX_I ((1 << (N-1)) - 1) // maximum value of signed N-bit number
// We use the following three pointers to access data, which can be changed
// when the program pauses. We need to make sure to have the RAM set up
// for these addresses.
int *pIn = (int *)0x20010000U; // the value of In should be -1, 0, or 1.
int *pX0 = (int *)0x20010004U; // X0 and X1 should be N-bit integers.
int *pX1 = (int *)0x20010008U;
int main(void) {
enum progState{State1 = 1, State2, State3, State4};
enum progState cState = State1; // Current State
bool dataReady = false;
bool cFlg, vFlg;
int result;
while (1) {
dataReady = false;
// Check if the data are legitimate
while (!dataReady) {
printf("Halt program here to provide correct update of data\n");
printf("In should be -1, 0, and 1 and ");
printf("X0 and X1 should be N-bit SIGNED integers\n");
if (((-1 <= *pIn) && (*pIn <= 1)) &&
((MIN_I <= *pX0) && (*pX0 <= MAX_I)) &&
((MIN_I <= *pX1) && (*pX1 <= MAX_I))) {
dataReady = true;
}
}
printf("Your input: In = %d, X0 = %d, X1 = %d \n", *pIn, *pX0, *pX1);
switch (cState) {
case State1:
result = s1_add_uintN(*pX0, *pX1, &cFlg);
printf("State = %d, rslt = %d, Cflg = %d\n", cState, result, cFlg);
cState += *pIn;
if (cState < State1) cState += State4;
break;
case State2:
result = s2_add_intN(*pX0, *pX1, &vFlg);
printf("State = %d, rslt = %d, Vflg = %d\n", cState, result, vFlg);
cState += *pIn;
break;
case State3:
case State4:
default:
printf("Error with the program state\n");
}
}
}
int s1_add_uintN(int x0, int x1, bool *c_flg) {
if (x0 < 0) x0 = x0 + MAX_U + 1;
if.
The Roman Empire A Historical Colossus.pdfkaushalkr1407
The Roman Empire, a vast and enduring power, stands as one of history's most remarkable civilizations, leaving an indelible imprint on the world. It emerged from the Roman Republic, transitioning into an imperial powerhouse under the leadership of Augustus Caesar in 27 BCE. This transformation marked the beginning of an era defined by unprecedented territorial expansion, architectural marvels, and profound cultural influence.
The empire's roots lie in the city of Rome, founded, according to legend, by Romulus in 753 BCE. Over centuries, Rome evolved from a small settlement to a formidable republic, characterized by a complex political system with elected officials and checks on power. However, internal strife, class conflicts, and military ambitions paved the way for the end of the Republic. Julius Caesar’s dictatorship and subsequent assassination in 44 BCE created a power vacuum, leading to a civil war. Octavian, later Augustus, emerged victorious, heralding the Roman Empire’s birth.
Under Augustus, the empire experienced the Pax Romana, a 200-year period of relative peace and stability. Augustus reformed the military, established efficient administrative systems, and initiated grand construction projects. The empire's borders expanded, encompassing territories from Britain to Egypt and from Spain to the Euphrates. Roman legions, renowned for their discipline and engineering prowess, secured and maintained these vast territories, building roads, fortifications, and cities that facilitated control and integration.
The Roman Empire’s society was hierarchical, with a rigid class system. At the top were the patricians, wealthy elites who held significant political power. Below them were the plebeians, free citizens with limited political influence, and the vast numbers of slaves who formed the backbone of the economy. The family unit was central, governed by the paterfamilias, the male head who held absolute authority.
Culturally, the Romans were eclectic, absorbing and adapting elements from the civilizations they encountered, particularly the Greeks. Roman art, literature, and philosophy reflected this synthesis, creating a rich cultural tapestry. Latin, the Roman language, became the lingua franca of the Western world, influencing numerous modern languages.
Roman architecture and engineering achievements were monumental. They perfected the arch, vault, and dome, constructing enduring structures like the Colosseum, Pantheon, and aqueducts. These engineering marvels not only showcased Roman ingenuity but also served practical purposes, from public entertainment to water supply.
Model Attribute Check Company Auto PropertyCeline George
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A Strategic Approach: GenAI in EducationPeter Windle
Artificial Intelligence (AI) technologies such as Generative AI, Image Generators and Large Language Models have had a dramatic impact on teaching, learning and assessment over the past 18 months. The most immediate threat AI posed was to Academic Integrity with Higher Education Institutes (HEIs) focusing their efforts on combating the use of GenAI in assessment. Guidelines were developed for staff and students, policies put in place too. Innovative educators have forged paths in the use of Generative AI for teaching, learning and assessments leading to pockets of transformation springing up across HEIs, often with little or no top-down guidance, support or direction.
This Gasta posits a strategic approach to integrating AI into HEIs to prepare staff, students and the curriculum for an evolving world and workplace. We will highlight the advantages of working with these technologies beyond the realm of teaching, learning and assessment by considering prompt engineering skills, industry impact, curriculum changes, and the need for staff upskilling. In contrast, not engaging strategically with Generative AI poses risks, including falling behind peers, missed opportunities and failing to ensure our graduates remain employable. The rapid evolution of AI technologies necessitates a proactive and strategic approach if we are to remain relevant.
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June 3, 2024 Anti-Semitism Letter Sent to MIT President Kornbluth and MIT Cor...Levi Shapiro
Letter from the Congress of the United States regarding Anti-Semitism sent June 3rd to MIT President Sally Kornbluth, MIT Corp Chair, Mark Gorenberg
Dear Dr. Kornbluth and Mr. Gorenberg,
The US House of Representatives is deeply concerned by ongoing and pervasive acts of antisemitic
harassment and intimidation at the Massachusetts Institute of Technology (MIT). Failing to act decisively to ensure a safe learning environment for all students would be a grave dereliction of your responsibilities as President of MIT and Chair of the MIT Corporation.
This Congress will not stand idly by and allow an environment hostile to Jewish students to persist. The House believes that your institution is in violation of Title VI of the Civil Rights Act, and the inability or
unwillingness to rectify this violation through action requires accountability.
Postsecondary education is a unique opportunity for students to learn and have their ideas and beliefs challenged. However, universities receiving hundreds of millions of federal funds annually have denied
students that opportunity and have been hijacked to become venues for the promotion of terrorism, antisemitic harassment and intimidation, unlawful encampments, and in some cases, assaults and riots.
The House of Representatives will not countenance the use of federal funds to indoctrinate students into hateful, antisemitic, anti-American supporters of terrorism. Investigations into campus antisemitism by the Committee on Education and the Workforce and the Committee on Ways and Means have been expanded into a Congress-wide probe across all relevant jurisdictions to address this national crisis. The undersigned Committees will conduct oversight into the use of federal funds at MIT and its learning environment under authorities granted to each Committee.
• The Committee on Education and the Workforce has been investigating your institution since December 7, 2023. The Committee has broad jurisdiction over postsecondary education, including its compliance with Title VI of the Civil Rights Act, campus safety concerns over disruptions to the learning environment, and the awarding of federal student aid under the Higher Education Act.
• The Committee on Oversight and Accountability is investigating the sources of funding and other support flowing to groups espousing pro-Hamas propaganda and engaged in antisemitic harassment and intimidation of students. The Committee on Oversight and Accountability is the principal oversight committee of the US House of Representatives and has broad authority to investigate “any matter” at “any time” under House Rule X.
• The Committee on Ways and Means has been investigating several universities since November 15, 2023, when the Committee held a hearing entitled From Ivory Towers to Dark Corners: Investigating the Nexus Between Antisemitism, Tax-Exempt Universities, and Terror Financing. The Committee followed the hearing with letters to those institutions on January 10, 202
Welcome to TechSoup New Member Orientation and Q&A (May 2024).pdfTechSoup
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1. Original Research Open Access
Evaluation of tensile, flexural and Impact strength of
natural and glass fiber reinforced hybrid composites
Ashik K P2*, Ramesh S. Sharma1 and Subhash Patil2
1Professor, Department of Mechanical Engineering RVCE,
Bengaluru, India.
2Research Scholar, Department of Mechanical Engineering
RVCE, Bengaluru, India.
*Correspondence: [email protected]
Abstract
The development of composite materials made up of natural
fibers is improving in engineering applications
such as Automotive, Marine and Aerospace, due to its
properties such as high specific strength, renewable,
non-abrasive, low cost, bio-degradability. Many researchers
have identified different natural fibers used
to substitute glass fiber, among them jute appears to be
favorable material because of its low cost, high
strength, high aspect ratio, good insulating and low thermal
conductivity. Hence the objective of this
research work was to evaluate the mechanical properties of
hybrid composites such as tensile strength,
f lexural strength and impact strength using static test methods
as per ASTM standards and Finite
Element Analysis was done to evaluate the properties of the
composite laminate and compared results of
FEA with experimental results. The composite laminates used
for the present investigation was fabricated
using hand layup technique. Incorporation of natural and glass
3. recently become attractive to researchers and scientists as an
alternative method for fibers reinforced composites. Among
natural fibers jute fiber appears to be promising material
because
it is inexpensive, high strength, high aspect ratio, good insulat-
ing and completely bio-degradable and recyclable. Consistency
of the composites were studied by Manuel Chiachio, et al., [1]
studied the basic structure of composite material and they
concluded that composite materials can be used in wide variety
of application such as automotive, aerospace and construction
applications. Michael Karus, et al., [2] has studied the demand
for natural fibers in automotive sector and interest in natural
fibers increasing day by day. Manufacturing of composite ma-
terials made by the natural fibers using compression moulding
has studied and natural fibers used in the transport segment
increasing in European market also explained. AninMemon,et
al., [3] has carried out investigation on jute reinforced poly-
mer composites. Composites fabricated using compression
moulding, when temperature increased effect of dispersion of
fiber from the mould increased. Furthermore tensile strength
decreased due to dispersion of fibers. Hence, investigation
concluded that temperature of mould effect the properties
Renewable Bioresources
ISSN 2052- 6237 | Volume 5 | Article 1
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4. Ashik K P et al. Renewable Bioresources 2017,
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2
doi: 10.7243/2052-6237-5-1
of composite material. Md. RashnalHossain et al., [4] studied
the properties of jute epoxy composite material because of
its properties compared synthetic fibers. In the investigation
composites were fabricated by using hand layup method and
composites were subjected to mechanical tests such as tensile
and flexural test, results concluded that tensile and flexural
strength of the composite depends on volume of fiber in the
composite material.Jansons et al., [5] evaluated the effect of
moisture and temperature as well as fatigue properties of
carbon fiber reinforced polymer composites. From the study
reveals that moisture absorption depends on the thickness of
the laminate and properties also depends on the thickness
of the composite. Kutty and Nandoet al., [6] investigated the
process parameters influences on the properties of Kevlar
and aramid composite laminates, investigation explains the
process parameters such as nip gap, friction ratio and mill
roll temperature maximum influence on the fiber sequence
and also influences the mechanical properties of composite.
Yuan et al., [7] studied the effect of modified Kevlar fibers
on the mechanical properties of wood-flour/polypropylene
composites. Study reveals that the addition of reinforcement
increases the properties of composites.Wang et al., [8] studied
static properties of synthetic fibers such as glass and Kevlar
reinforced composites from the investigation results shows
strength of the composite depends on the type of reinforce-
ment used in the composite laminate. After vast literature
survey carried on natural fibers and its propertiesits concluded
5. that lack of research progressed on jute fiber and its applica-
tion. Hence objective of this research work is to Evaluate the
Tensile, Flexural and Impact Strength of Natural and Glass
Fiber Reinforced Hybrid Composites.
Experimental
Material selection
In the present investigation jute fiber was procured from the
Jute Pragnya, Bengaluru, India. Glass Fiber was supplied by
Marchtech
Solution
s Bengaluru, India. The polyester resin
used in the investigation was general purpose polyester resin
fb-333 and the hardener used was Catalystmethyl ethyl ke-
tone peroxide (MEKP) and accelerator was cobalt napthenate.
Both resin and hardener procured from the commercial resin
supplier, Bengaluru, India. Figure 1 shows the Bi-Directional
jute and glass fiber mat.
Fabrication of composite laminate
Composite Laminate was fabricated by Hand layup technique.
The bi-directional jute fibre and the E-glass fibres were used
as reinforcement and Polyester was considered as matrix
material. Four laminates were prepared with different fiber
orientation as shown in Table 1. Bi woven fiber reinforce-
6. ments used for the laminate because these fibers gives better
strength compared to uni directional and chopped fibers Each
laminate included three layers of reinforcement in 00/900 Bi
woven fiber direction. Laminate L1 contains three layers of
Figure 1. Bi-Directional jute and glass fiber mat.
Laminate Composition
L1 100% Jute Fiber
L2 100% Glass Fiber
L3 60% Jute and 40% Glass Fiber
L4 60% Glass and 40% Jute Fiber
Table 1. Laminates and its composition.
jute fiber, laminate L2 contains three layers of glass fiber and
laminate L3 contains two layers of jute fiber and one layer of
glass fiber similarly laminate L4 contains two layers of glass
fiber and one layer of jute fiber.
The sticking of polyester resin to the surface was avoided
by spraying the release gel on the mould surface. In order to
obtain better surface finish, at both ends of themould, thin
plastic layer were placed for easy removing of laminate. As
per the mould size, E-glass fibers and woven mat jute fabrics
7. were cut for the reinforcement and positioned on the layer of
the mould after plastic layer. After reinforcement, polyester
resin taken in a liquid form was added carefully in appropri-
ate amount with hardener in the ratio 1:0.2:0.2 and resin was
poured onto the layer of reinforcement already positioned
on the mould. The polyester resin was evenly applied using
brush. The next layer of reinforcement was positioned on the
polyester resin with the help of roller with slight pressure on
the reinforcement-polyester layer to take out any air voids as
well as theleftover polyester resin on the mould. The process
was repeated for each layer of polyester and reinforcement,
until the necessary layers were placed. On the surface of fiber
and polyester resin plastic layer was placed, again for easy
removal of mould release gel was sprayed on the above layer
of the top mould and pressure was applied. After curing at the
temperature of 80˚C, the mould was removedand the ready
composite laminate was obtained and it was machined for
the required dimensions. Preparation of composite laminate
using hand layup technique is shown in the Figure 2.
Densities of the laminate calculated using the relation
weight of the laminate divided by area of the laminate. Densi-
ties of Laminate represented in the Table 2.
http://www.hoajonline.com/journals/pdf/2052-6237-5-1.pdf
8. http://dx.doi.org/10.7243/2052-6237-5-1
Ashik K P et al. Renewable Bioresources 2017,
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doi: 10.7243/2052-6237-5-1
Mechanical characterization
Tensile strength
Tensile test or tension test is a basic test in which a specimen
is subjected to uniaxial tension until the material fractures,
uniaxial tension refers to the force acting on the opposite faces
of the material in opposite direction with respect to each other
along the same axis. The material is placed between two grips
and is subjected to tensile or tension force. This force causes
the gauge length of the material to elongate and finally mate-
rial fractures. Thus, Elongation, final cross sectional area and
peak load of the material are obtained directly from tensile
test. In the present investigation,the tensile test laminates
were prepared asper ASTM: D3039(Dimension is 250×25×3
mm) and the testing was carried out using universal testing
machine Model: KIC-2-1000-C, it can withstand maximum
9. load of 10KN and machine was connected with a computer
and results are obtained in graphs and values are recorded
in the separate file. Figure 3 indicates the experimental set
up for tensile strengthtest.
Flexural strength
In the present investigation, laminates prepared as per ASTM:
D790 Standard.(Dimension is 127×12.7×3 mm) Flexural test
was carried in a three point flexural setup in universal test-
ing machine. Test carried to all four different compositions
of laminates. Figure 4 represent the loading setup of the
laminates for flexuraltest.
Table 2. Laminates and its composition.
Figure 2. Laminates fabricated using hand lay-up technique.
Figure 3. Experimental set up for tensile strengthtest.
Laminate Weight Wc
(in grams)
Density ρc
(g/cm3)
L1 699 1.23
10. L2 776 1.81
L3 727 1.62
L4 677 1.35
Figure 4. Loading arrangement of the specimens for
flexuraltest.
Finite element analysis
In the present investigation, static analysis of composites
was studied with the help of ANSYS 15. The modeling of
specimens was done in ANSYS considering element type as
SHELL 181, throughout the study. The element has four nodes
with six degrees of freedom at each node: translations in the
x, y, and z axes, and rotations about the x, y and z axes. Thus
each element has 24 degrees of freedom in total. The element
size of 2 was considered for meshing of specimen. Figure 5
represent the meshing used for the tensile and flexural test.
Using the simple rule-of-mixtures [9], elastic constants of the
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http://dx.doi.org/10.7243/2052-6237-5-1
Ashik K P et al. Renewable Bioresources 2017,
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11. 4
doi: 10.7243/2052-6237-5-1
unidirectional composite were calculated.
For bi-woven fiber reinforced lamina
Where UD and WF denote unidirectional fiber and woven
fiber respectively. After calculating the elastic properties of
Figure 5. Meshing Used for Tensile Test (a) and flexural test
(b).
(1)
(2)
(3)
(4)
(5)
12. (6)
(7)
(8)
(9)
(10)
(11)
(12)
unidirectional lamina in the equation 1-6, bi directional lamina
elastic properties were calculated using equation 7-12 [11].
Impact strength
In the present investigationimpact testing was carried in a
charpy impact setup. Composite laminate prepared for the
test as per ASTM: D256 standard. The effect of strain rate on
fracture and ductility of the material was analyzed. Figure 6
indicate the experimental set up and loading arrangement
of the specimens for impact test.
13. Figure 6. Experimental set up and loading arrangement of
the specimens for impact test.
Results and discussion
Tensile properties
In the investigation tensile test was carried out by put on
tensile load on the composite laminate. Four different volume
of fibers and resin were tested. In every test, three samples
were tested to achieve average values of same composition
of laminateand results were noted. The laminate was fixed
in the fixture of the machine and load was applied and the
corresponding change in length of the specimen wasrecorded.
The load was applied on the laminate until it breaks and peak
load, ultimate tensile strengths were recorded. After testing
stress and strain curve obtained from the software it was
recorded and load v/s displacement graphs were generated.
Figure 7 represent the tensile test specimens.
Figure 8 shows the tensile strength of four different lami-
nates with different percentage of fiber and resin content. It
can be observed from Figure 8 that tensile strength of the
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14. Ashik K P et al. Renewable Bioresources 2017,
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laminate 2 which include 100% of glass fiber shows higher
tensile strength compared all other laminates. Laminate with
higher volume of glass fiber in the laminate 4 shows better
strength compared to laminate 1 and laminate 2 with higher
volume of jute fiber. Hence, from the volume fraction of glass
fiber higher in the laminates gives higher tensile strength.
Flexural properties
Flexural test was carried in the same universal testing machine
by put on load in between the test length of the composite.
Test carried on the four different laminate and the various
parameters of flexural testing was determined. peak load was
recorded and load v/s displacement graphs were generated.
Figure 9 shows the fractured flexural specimens.
Figure 7. Tensile testing specimen of jute/glass fibre.
15. Figure 8. Variation of tensile strength for different fiber
percentage of laminates.
Figure 9. Fractured Flexural tested specimen.
Figure 10. Variation of flexural strength for different fiber
percentage of laminates.
Figure 10 shows the flexural strength of four different laminates
with different percentage of fiber and resin content. It can
be observed from Figure 10 flexural strength of laminate 2
shows higher flexural strength compared to other laminates.
It can be observed that laminate with higher percentage
shows glass fiber gives better tensile strength compared to
any other combinations.
Finite element analysis result
Finite element analysis carried using ANSYS to validate
the experimental tensile and flexural results [10]. It can be
observed that experimental results shows good agreement
with the ANSYS values. It was concluded that by assuming
uniform mixture and properties of the fibers in the entire
laminate, the tensile strength of L2 laminate (279MPa) was
17.9% higher than L4 laminate (229MPa), 44.6% higher than
L3 (154.5MPa) laminate and 72% higher than L1 laminate.
16. In case of flexural testing, flexural strength of L2 laminate
(373MPa) was 19.3% higher than L4 laminate (301MPa),
42.09%
higher than L3 (216MPa) laminate and 68.36% higher than
L1 laminate (118MPa). The results of tensile and flexural test,
both experimental and ANSYS are tabulated in Tables 3 and 4.
The Figure 11 shows the contour plots of von mises stress
Laminates Experimental (MPa) ANSYS (MPa) % Difference
L1 78 86.31 9.6
L2 279 271.78 2.5
L3 154 156.6 1.6
L4 229 221.67 3.2
Table 3. Tensile Strength of laminates.
Table 4. Flexural Strength of laminates.
Laminates Experimental (MPa) ANSYS (MPa) % Difference
L1 118 122.6 3.7
L2 373 380.09 1.8
L3 210 212.06 1.9
L4 301 305.07 1.3
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of L1, L2, L3 and L4 laminates for Tensile and flexural test
analysis respectively.
Impact strength
Charpy Impact Test was used to determine the impact prop-
erties of the material. The effect of strain rate on fracture
and ductility of the material ws analyzed. From the Figure 12
it can be observed that laminate 2 with 100% of glass fiber
absorbed more energy compared to other laminates because
of high volume of glass fiber in the laminates. Figure 13 shows
the energy absorbed in the impact testing of the laminates.
Conclusions
The Finite Element Analysis and experimental studies on
18. the mechanical properties of natural and syntheticfiber was
investigated. Effect of fiber loading and orientation on me-
Figure 11. Finite element tensile test analysis of Laminates
L1 (a), L2 (b), L3 (c) and L4 (d) for von mises stress.
Figure 12. Finite element Flexural test analysis of Laminates L1
(a), L2 (b), L3 (c) and L4 (d) for von mises stress.
Figure 13. Energy absorbed by the laminates in impact testing.
chanical properties of jute and glass fiber reinforced polymer
based hybrid composites led to the following conclusions:
In tensile test, laminate L1 with 100% of jute fiber shows
decrease in strength when compared with laminate L2 with
100% of Glass fiber.
In flexural test, composite laminate L3 & L4 with Jute and
Glass fiber orientation concludesimproved strength than
laminate L1. In the same way Laminate L4 shows improved
strength than laminate L3, because volume of glass fiber was
higher in the laminate.
The combination of reinforcement such as glass fiber and
19. jute fiber in composite laminates improves the mechanical
strength and this makes way to the increase of the utilization
of natural fibers in various applications.
Experimental results validated using Finite Element Analysis,
results from the analysis proved the experimental results.
From the present investigation it has been observed that
the composites with natural fiber and synthetic fiber increases
mechanical strength such as tensile strength, flexural strength,
impact strength of the composites with the increase in fiber
and also strengthsignificantlyvaried by the fiber composition.
Competing interests
The authors declare that they have no competing interests.
Authors’ contributions
Acknowledgement
Authors thankfully acknowledge Management, Principal
and Head of the Department, Mechanical Engineering,
R V College of Engineering for their constant support
and encouragement in carrying out this work.
Publication history
20. EIC: Saffa Riffat, University of Nottingham, UK.
Received: 30-Nov-2016 Final Revised: 14-Mar-2017
Accepted: 03-Apr-2017 Published: 18-Apr-2017
Authors’ contributions AKP RSS SP
Research concept and design -- ✓ --
Collection and/or assembly of data ✓ -- --
Data analysis and interpretation -- ✓ --
Writing the article ✓ -- --
Critical revision of the article -- ✓ --
Final approval of article -- ✓ --
Statistical analysis -- -- ✓
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21. References
1. Manuel Chiachio, Juan Chiachio and Guillermo Rus.
Reliability in
composites–A selective review and survey of current
development.
Composites: Part B. 2012; 43:902-913. | Article
2. Michael Karus and Markus Kaup. Natural Fibres in the
European
Automotive Industry. Journal of Industrial Hemp. 2008; 7:119-
131. |
Article
3. AninMemonaand AsamiNakai. Fabrication and Mechanical
Properties of
Jute Spun Yarn/PLA Unidirection Composite by Compression
Molding.
Energy Procedia. 2013; 34:830-838. | Article
4. Md. Rashnal Hossain, Md. AminulIslama, Aart Van Vuureab,
Ignaas
Verpoestb. Tensile behavior of environment friendly jute epoxy
laminated composite. Procedia Engineering. 2013; 56:782-788. |
Article
22. 5. Janson, K. Glejbøl, J. Rytter, A. N. Aniskevich, A. K.
Arnautov and
V. L. Kulakov. Effect of Water Absoption, Elevated
Temperatures
and Fatigue on the Mechanical Properties of Carbon-Fiber-
Reinforced Epoxy Composites for Flexible Risers. Mechanics of
composite material. 2002; 38:299-310. | Article
6. Sunil. K. N. Kutty and Golok. B. Nando. Mechanical
Properties of
Short Polyethylene Terephthalate Fiber-Thermoplastic
Polyurethane
Composite. International Journal of Polymeric Materials and
Polymeric
Biomaterials. 2006; 19:63-74.
7. Fei-pin Yuan, Rong-xian Ou, Yan-jun Xie and Qing-wen
Wang.
Reinforcing effects of modified Kevlar fiber on the mechanical
properties of wood-flour/polypropylene composites. Journal of
Forestry
Research. 2013; 24:149-153. | Article
8. Youjiang Wang, Jian Li and Dongming Zhao. Mechanical
23. properties of
fiber glass and Kevlar woven fabric reinforced composites.
Composite
Engineering. 1995; 5:1159-1175. | Article
9. Remko Akkerman. Laminate mechanics for balanced woven
fabrics.
Composites: Part B. 37:108-116. | Article
10. Vishnu Prasad, Ajil Joy, G. Venkatachalam, S.Narayanan
and S. Raja
kumar. Finite Element analysis of jute and banana fibre
reinforced
hybrid polymer matrix composite and optimization of design
parametersusing ANOVA technique. Procedia Engineering.
2014;
97:1116-1125. | Article
11. Mohammed F. Aly, I. G. M. Goda and Galal A. Hassan.
Experimental
Investigation of the Dynamic Characteristics of Laminated
Composite
Beams. Experimental Investigation of the Dynamic
Characteristics of
Laminated Composite Beams. | Pdf
24. Citation:
K P A, Sharma RS and Patil S. Evaluation of tensile,
flexural and Impact strength of natural and glass fiber
reinforced hybrid composites. Renew Bioresour. 2017;
5:1. http://dx.doi.org/10.7243/2052-6237-5-1
http://www.hoajonline.com/journals/pdf/2052-6237-5-1.pdf
http://dx.doi.org/10.7243/2052-6237-5-1
http://dx.doi.org/10.1016/j.compositesb.2011.10.007
http://dx.doi.org/10.1300/J237v07n01_10
https://doi.org/10.1016/j.egypro.2013.06.819
https://doi.org/10.1016/j.proeng.2013.03.196
https://doi.org/10.1023/A:1020024007414
https://doi.org/10.1007/s11676-013-0335-z
https://doi.org/10.1016/0961-9526(95)00100-2
http://dx.doi.org/10.1016/j.compositesb.2005.08.004
https://doi.org/10.1016/j.proeng.2014.12.390
http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.207.5
914&rep=rep1&type=pdf
http://dx.doi.org/10.7243/2052-6237-5-
1AbstractIntroductionExperimentalMaterial
selectionFabrication of composite laminateMechanical
characterizationTensile strengthFlexural strengthFinite element
analysisImpact strengthResults and discussionTensile
26. Department of Mechanical Engineering, National Institute of
Technology, Rourkela 769008, India
Abstract
During last few years, the interest in using natural fibers as
reinforcement in polymers has increased dramatically. Natural
fibers are not
only strong and lightweight but also relatively very cheap. In
this research work, an investigation has been carried out to
make use of jute
fiber, a natural fiber abundantly available in India. The present
work describes the development and characterization of a new
set of
natural fiber based polymer composites consisting of
bidirectional jute fiber mat as reinforcement and epoxy resin as
matrix material. The
composites are fabricated using hand lay-up technique and are
characterized with respect to their physical and mechanical
properties.
Experiments are carried out to study the effect of fiber loading
on the physical and mechanical behavior of these composites.
Result
shows the significant effect of fiber loading on the mechanical
properties of the composites. Also, the formation of voids in the
29. properties, corrosion resistance and low energy consumption
during fabrication [2]. Fiber reinforced composites made up of
carbon, boron, glass and kevlar fibers have been accepted
widely as the materials for structural and non-structural
applications [3].
Environmental concerns are increasing day by day and the
demand of replacing the existing synthetic fibers with the
biodegradable, renewable and low cost natural fibers for
fabrication of composite materials increases. In comparison to
the
traditional reinforcing materials natural fiber such as sisal, jute,
abaca, pineapple and coir has acceptable specific strength
properties, low density, low abrasion multi-functionality, good
thermal properties, enhanced energy recovery and cause less
skin and respiratory irritation [4, 5]. Pervaiz and Sain [6]
examined the energy consumption of glass and natural fibers,
and
they found that by using vegetal fibers in place of glass fibers,
energy could be saved at a rate of 60% per ton of product.
Jute, a natural fiber in polymer composites would be suitable
for the primary structural applications, such as indoor elements
in housing, temporary outdoor applications like low-cost
housing for defence and rehabilitation and transportation. The
insulating characteristics of jute may find applications in
30. automotive door/ceiling panels and panel separating the engine
and
passenger compartments [7].The use of natural fiber like jute
not only help us in ecological balance but can also provide
employment to the rural people in countries like India and
Bangladesh where jute is abundantly available.
In this study bi-directional fiber mat has been used for the
preparation of the composites. The purpose of this study is to
investigate the potential utilization of jute fiber as
reinforcement in polymer matrix composites. Also, the effect of
jute fiber
content on the physical and mechanical behavior of the
composites is investigated.
2. Experimental Details
2.1. Materials and Method
Bidirectional jute fiber mat has been obtained from the local
sources as a reinforcing material. Epoxy resin and the
corresponding hardner are supplied by Ciba Geigy India Ltd.
The polymers composites are fabricated by hand lay-up
technique. Composite specimens with different fiber loading (0,
12, 24, 36 and 48 wt %) were prepared and subjected to
postcuring for 24 hours at room temperature.
31. 2.2. Physical and Mechanical Characterization
The theoretical density of the composites can be obtained in
terms of the weight fractions and densities of the
constituents, and is given by Eq. (1)
1
(1)
/ /
ct
f f m mW W
ct, f and m correspond to the composites, fiber
and matrix, respectively.
Water immersion technique has been used to determine the
actual density of the prepared composites experimentally.
The volume fraction of voids in composites is given by the
32. relation
(2)ct ex
ct
v
where ex is the experimental density of the composite
fabricated.
Hardness measurement is done using a Rockwell-hardness tester
equipped with a steel ball indenter. Tensile test is
performed as per ASTM D 3039-76 test standards using
universal testing machine Instron 1195.Three point bend test is
carried out in the same machine at a cross head speed of 10
mm/min to obtain the flexural strength and inter laminar shear
strength (ILSS). Impact strength of the composites is evaluated
by a low velocity impact tests conducted in an impact tester
as per ASTM D 256 test standards.
3. Result and Discussion
3.1. Physical and Mechanical Properties
33. The theoretical density, experimental density and void fraction
(in percentage) are reported in the Table 1. The presence
of the voids may affect the mechanical properties of the
composites. The void formation in the polymer composites can
563 Vivek Mishra and Sandhyarani Biswas / Procedia
Engineering 51 ( 2013 ) 561 – 566
occur due to air entrapment during the preparation of resin
system and moisture absorption during the material processing
or
storage. A higher void content in the composites shows that
resin has not thoroughly surrounded the fibers and resulting in
weaker interfacial strength which in turn reduces strength and
stiffness of composites, mutual abrasion of fiber leads to fiber
fracture and damage and crack initiation and growth due to void
coalescence[8]. From Table 1 it is found that pure epoxy
has the minimum void content, with the addition of 12 wt. %
fiber the void content increases instantly to 5.312 %. But with
the further increase in the fiber content from 12 wt. % to 48 wt.
% the void content of the specimens decreases. The
theoretical density of the composites increases as the fiber
loading increases.
34. Table 1. Comparison between Experimental density and
Theoretical density
BJFE: bidirectional jute fiber epoxy, BD: bidirectional
Figure 1 shows the effect of fiber loading on the hardness of
composites. It has been found that the hardness of the
composite increases with the increase in the fiber loading. In
general the fibers increase the modulus of composite which in
turn increases the hardness of fiber. This is because hardness is
a function of relative fiber volume and modulus [9]. Surface
hardness value of 40 HRB is obtained from pure epoxy
specimen. The surface hardness value increases by 77% with the
incorporation of 12 wt. % fiber in the matrix. The maximum
surface hardness value of 85.5 HRB is obtained fro m
bidirectional jute epoxy composites reinforced with 48 wt. % of
jute fiber.
Fig 1. Effect of fiber loading on hardness of composites
The variation in tensile strength and tensile modulus of
35. composite with increase in fiber content is shown in Fig 2. It is
clearly visible that with the increase in fiber content in the
epoxy matrix, the tensile strength and modulus also increases.
There is a proper transmission and distribution of the applied
stress by the epoxy resin resulting in higher strength. Similar
observations have been made by Bijwe [10] in case of aramid
fabric/polyethersulfone composites. The bidirectional jute
fiber composite can bear higher load before failure compared to
neat or unfilled epoxy. The tensile strength varies from 43
MPa to 110 MPa and tensile modulus from 0.15 GPa to 4.45
GPa with the fiber varies from 0 to 48 wt%.
The result obtained from the three point bend test is shown in
Fig 3. It has been found that there is a reduction in the
flexural properties of specimen with 12 wt. % fiber loading.
Similar observations have also been made by Dong and Davies
[11]. According to their study, the reduction in the flexural
properties of the composites is due to weak interfacial bonding
and existence of voids. The flexural strength and modulus of the
composites increases with the increase in the fiber loading
Designation
Composite composition
Theoretical
37. obtained at 48 wt. % of fiber loading. The flexural strength and
modulus of 48 wt. % fiber loading are increased by 20 %
and 37 % in comparison to the neat epoxy. The jute fiber
inclusions enhance the load bearing capacity and ability to
withstand bending of the composites [12].
The effect of fiber loading on the inter-laminar shear strength
(ILSS) of the jute epoxy composite is shown in Fig 4. The
ILSS value decreases drastically for the composites with fiber
loading from 0 wt. % to 12 wt. %, however it increases on
further increase in fiber loading from 12 wt. % to 48 wt. %. The
maximum ILSS of 66.5 MPa is obtained at 48 wt. % fiber
loading.
Fig 2. Effect of fiber loading on tensile strength and modulus of
composites
Fig 3. Effect of fiber loading on flexural strength and modulus
of composites
Fig 4. Effect of fiber loading on inter-laminar shear strength of
composites
38. 565 Vivek Mishra and Sandhyarani Biswas / Procedia
Engineering 51 ( 2013 ) 561 – 566
The impact strength of the bidirectional jute epoxy composites
in shown in Fig 5. The energy absorbed by the composite
due to impact load is 2.87, 3.69, 4.264, 4.59 times of pure
epoxy matrix for composites with fiber content of 12 wt. %, 24
wt.%, 36 wt.% and 48 wt.% respectively. The maximum impact
strength is of 4.875 J in the case of composite with 48 wt.%
of fiber loading. The increase in the impact strength with the
increased fiber loading may be due to the fact that more energy
will have to be used up to break the coupling between the
interlaced fiber bundles. Good adhesion between the fiber and
matrix is also responsible for the good resistance to crack
propagation during impact test. The increased fiber content will
increase the contact area between the fiber and matrix, if there
is good impregnation of fibers in the resin. At higher fiber
loading the impact transfer should be more efficient [15].
39. Fig 5. Effect of fiber loading on impact strength of composites
4. Conclusion
The following conclusions have been drawn from the study of
the jute epoxy composite:
1. Successful fabrication of the bidirectional jute fiber
reinforced epoxy composite has been done by the hand lay-up
technique.
2. The minimum and maximum void content are in neat epoxy
and 12 wt. % fiber loading specimens respectively. It is also
found from the study that the void content decreases with the
increase in fiber loading.
3. The hardness, tensile properties and impact strength of the
jute-epoxy composites increases with the increase in fiber
loading.
4. The properties like flexural strength and inter-laminar shear
strength are greatly influenced by the void content of the
composites. It has been found that these properties reduced
from 0 wt.% to 12 wt.% fiber loading and with the reduction in
the void content from 12 wt.% to 48 wt.% the properties are
improved.
References
40. [1] Zaman H. U., Khan A., Khan R. A., Huq T., Khan M. A.,
Shahruzzaman Md., Mushfequr Rahman Md., Al-Mamun Md.,
and Poddar P., 2010.
Preparation and Characterization of Jute Fabrics Reinforced
Urethane Based Thermoset Composites: Effect of UV Radiation,
Fibers and Polymers,
11(2), p. 258.
[2] Jawaid M., Abdul Khalil H.P.S., Abu Bakar A., Noorunnisa
Khanam P., 2011. Chemical resistance, void content and tensile
properties of oil
palm/jute fibre reinforced polymer hybrid composites, Materials
and Design, 32, p. 1014.
[3] Gowda T. M., Naidu A.C.B., Rajput C., 1999. Some
mechanical properties of untreated jute fabric-reinforced
polyester composites, Composites: Part
A, 30, p. 277.
[4] Huq T., Khan A., Akter T., Noor N., Dey K., Sarker B.,
Saha M.,2011. Thermo-mechanical, Degradation, and Interfacial
Properties of Jute Fiber-
reinforced PET-based Composite, DOI:
10.1177/0892705711401846.
41. [5] Chin C.W., Yousif B.F., 2009.Potential of kenaf fibres as
reinforcement for tribological applications, Wear, 267, p. 1550.
[6] Pervaiz M., Sain M.M., 2003. Carbon storage potential in
natural fibre composites, Resources Conservation and Recycling
39(4), p.325.
[7] Khondker O. A., Ishiaku U S., Nakai A., Hamada H., 2005.
Fabrication and Mechanical Properties of Unidirectional Jute/PP
Composites Using Jute
Yarns by Film Stacking Method, Journal of Polymers and the
Environment, 13(2) , p. 115.
[8] Boey F.Y.C., 1990. Reducing the Void Content and its
Variability in Polymeric Fibre Reinforced Composite Test
Specimens using a Vacuum
Injection Moulding Process, Polymer Testing, 9 , p. 363.
[9] Srinivasa C.V., Bharath K.N., 2011.Impact and Hardness
Properties of Areca Fibre-Epoxy Reinforced Composites,
Journal of Material Science and
566 Vivek Mishra and Sandhyarani Biswas / Procedia
Engineering 51 ( 2013 ) 561 – 566
42. Environment, 2(4), p. 351.
[10] Bijwe J., Awtade S., Satapathy B.K., Ghosh A., 2004.
Influence of concentration of aramid fabric on abrasive wear
performance of polyethersulfone
composites, Tribology Letters, 17 (2), p. 187.
[11] Dong C., Davies I.J., 2011.Flexural Properties of Wheat
Straw Reinforced Polyester Composites, American Journal of
Materials Science, 1(2), p. 71.
[12] Mantry S., Satapathy A., Jha A.K., Singh S.K., Patnaik A.,
2010. Processing and Characterization of Jute Epoxy
Composites Reinforced with SiC
Derived from Rice Husk, 29(18), p. 2869.
[13] Åkesson D., Skrifvars M., Seppälä J., Turunen M.,
2011.Thermoset Lactic Acid-Based Resin as a Matrix for Flax
Fibers, Journal of Applied Polymer
Science, 119, p. 3004.
43. Composites: Part B 42 (2011) 856–873
Contents lists available at ScienceDirect
Composites: Part B
j o u r n a l h o m e p a g e : w w w . e l s e v i e r . c o m / l o c
a t e / c o m p o s i t e s b
A review on the tensile properties of natural fiber reinforced
polymer composites
H. Ku ⇑ , H. Wang, N. Pattarachaiyakoop, M. Trada
Centre of Excellence in Engineered Fibre Composites and
Faculty of Engineering, University of Southern Queensland,
Australia
a r t i c l e i n f o
Article history:
Received 15 March 2010
Received in revised form 19 November 2010
Accepted 8 January 2011
Available online 15 January 2011
Keywords:
A. Polymer-matrix composites (PMCs)
B. Mechanical properties
44. D. Mechanical testing
E. Compression moulding
1359-8368/$ - see front matter � 2011 Elsevier Ltd. A
doi:10.1016/j.compositesb.2011.01.010
⇑ Corresponding author. Tel.: +61 31 445 2485; fax
E-mail address: [email protected] (H. Ku).
a b s t r a c t
This paper is a review on the tensile properties of natural fiber
reinforced polymer composites. Natural
fibers have recently become attractive to researchers, engineers
and scientists as an alternative reinforce-
ment for fiber reinforced polymer (FRP) composites. Due to
their low cost, fairly good mechanical prop-
erties, high specific strength, non-abrasive, eco-friendly and
bio-degradability characteristics, they are
exploited as a replacement for the conventional fiber, such as
glass, aramid and carbon. The tensile prop-
erties of natural fiber reinforce polymers (both thermoplastics
and thermosets) are mainly influenced by
the interfacial adhesion between the matrix and the fibers.
Several chemical modifications are employed
to improve the interfacial matrix–fiber bonding resulting in the
enhancement of tensile properties of the
45. composites. In general, the tensile strengths of the natural fiber
reinforced polymer composites increase
with fiber content, up to a maximum or optimum value, the
value will then drop. However, the Young’s
modulus of the natural fiber reinforced polymer composites
increase with increasing fiber loading. Khoa-
thane et al. [1] found that the tensile strength and Young’s
modulus of composites reinforced with
bleached hemp fibers increased incredibly with increasing fiber
loading. Mathematical modelling was
also mentioned. It was discovered that the rule of mixture
(ROM) predicted and experimental tensile
strength of different natural fibers reinforced HDPE composites
were very close to each other. Halpin–
Tsai equation was found to be the most effective equation in
predicting the Young’s modulus of compos-
ites containing different types of natural fibers.
� 2011 Elsevier Ltd. All rights reserved.
1. Introduction applicable for aerospace, leisure, construction,
sport, packaging
A fiber reinforced polymer (FRP) is a composite material con-
sisting of a polymer matrix imbedded with high-strength fibers,
such as glass, aramid and carbon [2]. Generally, polymer can be
classified into two classes, thermoplastics and thermosettings.
46. Thermoplastic materials currently dominate, as matrices for bio-
fibers; the most commonly used thermoplastics for this purpose
are polypropylene (PP), polyethylene, and poly vinyl chloride
(PVC); while phenolic, epoxy and polyester resins are the most
commonly used thermosetting matrices [3]. In the recent
decades,
natural fibers as an alternative reinforcement in polymer
compos-
ites have attracted the attention of many researchers and
scientists
due to their advantages over conventional glass and carbon
fibers
[4]. These natural fibers include flax, hemp, jute, sisal, kenaf,
coir,
kapok, banana, henequen and many others [5]. The various
advan-
tages of natural fibers over man-made glass and carbon fibers
are
low cost, low density, comparable specific tensile properties,
non-abrasive to the equipments, non-irritation to the skin,
reduced
energy consumption, less health risk, renewability, recyclability
and bio-degradability [3]. These composites materials are
suitably
ll rights reserved.
47. : +61 31 446 9556.
and automotive industries, especially for the last mentioned
appli-
cation [3,6]. However, the certain drawback of natural
fibers/poly-
mers composites is the incompatibility between the hydrophilic
natural fibers and the hydrophobic thermoplastic matrices. This
leads to undesirable properties of the composites. It is therefore
necessary to modify the fiber surface by employing chemical
mod-
ifications to improve the adhesion between fiber and matrix [3].
There are many factors that can influence the performance of
natural fiber reinforced composites. Apart from the hydrophilic
nature of fiber, the properties of the natural fiber reinforced
com-
posites can also be influenced by fiber content/amount of filler.
In
general, high fiber content is required to achieve high
performance
of the composites. Therefore, the effect of fiber content on the
properties of natural fiber reinforced composites is particularly
sig-
nificance. It is often observed that the increase in fiber loading
48. leads to an increase in tensile properties [7]. Another important
factor that significantly influences the properties and interfacial
characteristics of the composites is the processing parameters
used. Therefore, suitable processing techniques and parameters
must be carefully selected in order to yield the optimum
composite
products. This article aims to review the reported works on the
ef-
fects of fiber loading, chemical treatments, manufacturing
techniques and process parameters on tensile properties of
natural
fiber reinforced composites.
http://dx.doi.org/10.1016/j.compositesb.2011.01.010
mailto:[email protected]
http://dx.doi.org/10.1016/j.compositesb.2011.01.010
http://www.sciencedirect.com/science/journal/13598368
http://www.elsevier.com/locate/compositesb
H. Ku et al. / Composites: Part B 42 (2011) 856–873 857
2. Tensile properties
Generally, the tensile properties of composites are markedly
improved by adding fibers to a polymer matrix since fibers have
49. much higher strength and stiffness values than those of the
matri-
ces as shown in Tables 1–3 [3,8].
Consider the tensile strength of S-glass from Table 1, and that
of
polypropylene (PP) from Table 2 and that of polyester resin
from
Table 3, it can be found that the tensile strength of the fiber
(S-glass) is 75–150 times higher than those of the matrices (PP
and polyester resin). It can also be found that the Young’s
modulus
of the fiber (S-glass) is 80–160 times higher than those of the
matrices (PP and polyester resin) [3–8].
In general, higher fiber content is desired for the purpose of
achieving high performance of short fiber reinforced polymer
com-
posites (SFRP) [7]. It is often observed that the presence of
fiber or
other reinforcement in the polymeric matrix raises the
composite
strength and modulus [5]. Therefore, the effect of fiber content
on the tensile properties of fiber reinforced composites is of
partic-
50. ular interest and significance for many researchers [7].
Nonwoven mats from hemp and polypropylene fibers in various
proportions are mixed and hot pressed to make composite
materi-
als. The effect of hemp fiber content and anisotropy are
examined
on the basis of tensile properties of the resultant composite
materials. The tensile strength, with fibers in the perpendicular
direction, tended to decrease with increasing hemp fiber content
(a maximum decrease of 34% at 70% of hemp) as depicted in
Fig. 1. Whereas, the tensile strength, with fibers in the parallel
direction, showed a different trend and a maximum value was
found with increasing fiber loading. It was found that the
tensile
strength of composites with fibers in the perpendicular direction
was 20 – 40% lower than those of composites with fibers in
parallel
direction. Since the fibers lay perpendicular to the direction of
load,
they cannot act as load bearing elements in the composite
matrix
structure but become potential defects which could cause
failure.
As expected, better tensile properties are found in the
51. specimens
cut from the composite sheets parallel to the direction of
carding
as depicted in Fig. 1 [9].
In general, the Young’s modulus of the composite materials in-
crease with an increase in fiber content, reaching a maximum
va-
lue at 50% hemp fiber loading and then decreasing slightly at
70% hemp fiber content. The Young’s modulus was almost two
and a half times higher at 50% hemp fiber loading than at 0%
fiber
content, i.e. pure PP as depicted in Fig. 2 [9].
Fig. 3 illustrated the tensile strength of 20-mesh hardwood, 40-
mesh hardwood, flax and rice hull fibers reinforced HDPE
compos-
ites. Li et al. [5] reported that flax fiber content from 10% to
30% by
mass was mixed with high-density polyethylene (HDPE) by
extru-
sion and injection moulding to produce bio-composites. The re-
Table 1
Properties of selected natural and manmade fibers [adapted from
3, 8].
52. Fiber Density (g/cm3) Elongation (%)
Cotton 1.5–1.6 7.0–8.0
Jute 1.3 1.5–1.8
Flax 1.5 2.7–3.2
Hemp 1.47 2–40
Kenaf 1.45 1.6
Ramie N/A 3.6–3.8
Sisal 1.5 2.0–2.5
Coir 1.2 30
Softwood kraft pulp 1.5 4.4
E-glass 2.5 0.5
S-glass 2.5 2.8
Aramid (Std.) 1.4 3.3–3.7
Carbon (Std. PAN-based) 1.4 1.4–1.8
sults showed that increasing fiber content resulted in increasing
tensile properties initially as depicted in Fig. 3. It peaked at
20%
by volume; it then dropped. However, the elongation at break of
the composites showed the reverse trend as depicted in Fig. 4
[5].
The tensile strengths of 40-mesh hardwood fibers reinforced
53. HDPE composites increased gradually, and up to a maximum at
25% of fiber loading by volume, and then dropped back as
depicted
in Fig. 3 [11]. On the other hand, the tensile strengths of 20-
mesh
hardwood fibers reinforced HDPE composites reduced with
increasing fiber loading [11]. This is totally different from that
of
40-mesh hardwood fibers. The tensile strengths of rice hull
fibers
reinforced HDPE composites were shown in Fig. 3 [10]; the
behaviour of the curve was more or less the same as those found
in 20-mesh hardwood but it has a maximum tensile strength at
5% by volume of fiber content [10]. The tensile strengths
decreased
with increasing particulate loading slightly [10].
Fig. 5 showed the Young’s modulus of 20-mesh hardwood, 40-
mesh hardwood, flax and rice hull fiber reinforced HDPE
compos-
ites with varying percentage by volume of fiber loading. It can
be
found that the Young’s modulus of 20-mesh and 40-mesh
hardwood fibers reinforced HDPE composites with fiber loading
of 0–40 wt.% [11]. The value increased with increasing fiber
54. load-
ing. Up to 30% volume fraction of hardwood, the Young’s
moduli
of 20-mesh hardwood fiber composites were lower than their
counterparts. After 35% volume fraction of hardwood, the
Young’s
moduli of 20-mesh hardwood fiber composites were higher than
their counterparts. Fig. 5 also illustrated the Young’s modulus
of
flax fibers reinforced HDPE composites with fiber loading of 0–
40% vol. [5]. It can be found that the Young’s modulus
increased
with increasing fiber content [5]. The Young’s modulus of rice
hulls
fibers reinforced HDPE composites with fiber loading of 0–40%
vol.
was depicted in Fig. 5 [10]. The trends of all the curves for Fig.
5
were more or less the same as, i.e. the values of the Young’s
modulus increased progressively with increasing fiber loading.
However, the largest increase with increasing fiber content was
for flax fiber reinforced composites, while the least increase
was
for rice hull fiber reinforced composites.
55. The dependence of tensile properties of micro winceyette fiber
reinforced thermoplastic corn starch composites on fiber
contents
was studied. Fig. 6 illustrated that with the increase fiber
content
from 0% to 20 wt.%, the tensile strength was approximately
trebled
to 150 MPa [12]. The increase was progressive. However, the
elon-
gation of the composites decreased with increasing fiber loading
as
depicted in Fig. 7. The elongation dropped significantly
between fi-
ber loading of 0–10% by weight; after this the decrease was
very
slightly. On the other hand, the energy at break of the
composites
decreased slightly from neat resin to 5 wt.% of fiber and
dropped
significantly from 5% to 10% by weight of fiber as depicted in
Fig. 8; after this there was a slight increase [12].
Tensile strength (MPa) Elastic modulus (GPa) Refs.
400 5.5–12.6 [6,7]
393–773 26.5 [6]
58. resin
Epoxy
Density (g/cm3) 1.2–1.5 1.2–1.4 1.1–1.4
Elastic modulus (GPa) 2–4.5 3.1–3.8 3–6
Tensile strength (MPa) 40–90 69–83 35–100
Compressive strength (MPa) 90–250 100 100–
200
Elongation (%) 2 4–7 1–6
Cure shrinkage (%) 4–8 N/A 1–2
Water absorption
(24 [email protected] �C)
0.1–0.3 0.1 0.1–0.4
Izod impact strength (J/m) 0.15–3.2 2.5 0.3
Fig. 1. Tensile strength of polypropylene/hemp fibres with
varying percentage by
weight of fibres [adapted from 9].
Fig. 2. Young’s modulus of polypropylene/hemp fibres with
varying percentage by
59. weight of fibres [adapted from 9].
Fig. 3. Tensile strength of 20-mesh hardwood, 40-mesh
hardwood, flax and rice
hull fibres reinforced HDPE composites [adapted from 5, 10 and
11].
858 H. Ku et al. / Composites: Part B 42 (2011) 856–873
Fig. 9 illustrated that with the increase of fiber content from 0%
to 20 wt.%, the Young’s modulus was approximately trebled to
140 MPa [12]. From 0% to 10% by weight of fiber loading, the
Young’s modulus was steady but increased progressively after
that
[12].
Khoathane et al. [1] found that increasing the amount of
bleached hemp fiber (0–30 w/t%) resulted in the initial increase
of tensile strength of the fiber reinforced 1-
pentene/polypropylene
(PP1) copolymer composite at 5% fiber content to 30 MPa from
20 MPa for the neat resin as depicted in Fig. 10. The tensile
strength
then dropped to a low 23 MPa at 20% fiber loading [1]. After
this,
the tensile strength increased again and its value was about at
60. par with that of 5% fiber content when the fiber was 30% [1].
Fig. 11 illustrated the effect of fiber contents on Young’s
modulus
of bleached hemp fiber reinforced PP1 composites [1]. The
value
of the Young’s modulus increased by over twice from 1.3 GPa
(neat
resin) to 4.4 GPa (30% w/t) [1].
Long-discontinuous natural fibers of kenaf and of jute rein-
forced polypropylene (PP) composites fabricated by carding and
hot pressing process with fiber weight fraction varying from
10%
to 70% in steps of 10% were studied [13]. The experimental
results
illustrated that the tensile and modulus strength of both kenaf
and
jute fiber reinforced PP composites increased with increasing
fiber
loading and a maximum was reached before falling back at
higher
fiber weight fraction. These were illustrated in Figs. 12 and 13
[13].
From the above citations and discussions, it can be found that
61. the values of the tensile strength of natural fiber reinforced
com-
posites increased with increasing fiber loading up to a maximum
or optimum value before falling back. However, it is generally
true
that the values of the Young’s modulus increased progressively
with increasing fiber loading. On the other hand, some
researchers
found totally the opposite trend to the increase of composite
strength with increasing fiber content. This can be attributed to
many factors such as incompatibility between matrix and fibers,
improper manufacturing processes, fiber degradation and others.
Fig. 4. Tensile elongation of bio-composites vs. fiber mass
concentration [adapted from 5].
Fig. 5. Young’s modulus of 20-mesh hardwood, 40-mesh
hardwood, flax and rice hull fibre reinforced HDPE composites
with fibre loadings of 0–40% vol. [adapted from 5, 10
and 11].
0
63. tr
en
gt
h
(M
P
a)
Fig. 6. The effect of fiber content on the tensile strength of
micro winceyette fiber
reinforced thermoplastic corn starch composites [adapted from
12].
0
20
40
60
64. 80
100
120
0 5 10 15 20
Fiber content by weight
E
lo
ng
at
io
n
(%
)
Fig. 7. The effect of fiber content on the elongation of micro
winceyette fiber
reinforced thermoplastic corn starch composites [adapted from
65. 12].
H. Ku et al. / Composites: Part B 42 (2011) 856–873 859
The hydrophilic nature of natural fibers is incompatible with
hydrophobic polymer matrix and has a tendency to form aggre-
gates. These hydrophilic fibers exhibit poor resistant to
moisture,
which lead to high water absorption, subsequently resulting in
poor tensile properties of the natural fiber reinforced
composites.
Moreover, fiber surfaces have waxes and other non-cellulosic
sub-
stances such as hemi-cellulose, lignin and pectin, which create
poor adhesion between matrix and fibers. Therefore, in order to
improve and develop natural fiber reinforced polymer
composites
with better tensile properties, it is necessary to increase fibers
hyp-
hobicity by introducing the natural fibers to surface chemical
mod-
ification (surface treatment). The fiber modification is
attempted to
improve fibers hydrophobic, interfacial bonding between matrix
and fiber, roughness and wettability, and also decrease moisture
absorption, leading to the enhancement of tensile properties of
66. the composites [13–17].
The different surface chemical modifications, such as chemical
treatments, coupling agents and graft co-polymerization, of
natural
fibers aimed at improving the tensile properties of the
composites
were performed by a number of researchers. Alkali treatment,
also
called mercerization, is one of the most popular chemical treat-
ments of natural fibers. Sodium hydroxide (NaOH) is used in
this
method to remove the hydrogen bonding in the network
structure
of the fibers cellulose, thereby increasing fibers surface
roughness
[13]. This treatment also removes certain amount of lignin, wax
and oils covering the external surface of the fibers cell wall,
0
50
68. )
Fig. 8. The effect of fiber contents on the energy at break of
micro winceyette fiber
reinforced thermoplastic corn starch composites [adapted from
12].
0
20
40
60
80
100
120
140
160
69. 0 5 10 15 20
Fiber content by weight
Y
ou
ng
's
M
od
ul
us
(N
/m
m
2)
Fig. 9. The effect of fiber contents on the Young’s modulus of
micro winceyette fiber
reinforced thermoplastic corn starch composites [adapted from
71. ile
s
tr
en
gt
h
(M
P
a)
Fig. 10. The effect of fiber contents on tensile strength of
bleached hemp fiber
reinforced PP1 composites [adapted from 1].
0
0.5
1
1.5
2
73. P
a)
Fig. 11. The effect of fiber contents on Young’s modulus of
bleached hemp fiber
reinforced PP1 composites [adapted from 1].
860 H. Ku et al. / Composites: Part B 42 (2011) 856–873
depolymerises the native cellulose structure and exposes the
short
length crystallites [14]. Acrylic acid treatment was also reported
to
be effective in modifying the natural fibers surface. A study on
flax
fibers-reinforced polyethylene bio-composites by Li et al. found
that the efficiency of such a treatment was higher than alkali
and
silane treatment [14].
The chemical coupling method is also one of the important
chemical methods, which improve the interfacial adhesion. In
this
method the fiber surface is treated with a compound that forms
a
74. bridge of chemical bonds between fiber and matrix. The
chemical
composition of coupling agents allows them to react with the
fiber
surface forming a bridge of chemical bonds between the fiber
and
matrix. Most researchers found these treatments were effective
and showed better interfacial bonding [13]. Among different
cou-
pling agents, maleic anhydride is the most commonly used. In
gen-
eral, the literature reports improvements in tensile strength and
elongation at break when maleic anhydride grafted matrices are
used as compatibilizers (coupling agent) [15].
Hu and Lim [18] investigated that alkali treatment significantly
improved the tensile properties of hemp fiber reinforced
polylactic
acid (PLA) compare to those untreated. Figs. 14 and 15 showed
that
the composites with 40% volume fraction of alkali treated fiber
have the best tensile properties. The tensile strength and tensile
modulus of the composites with 40% treated fiber are 54.6 MPa
and 85 GPa respectively, which are much higher than neat PLA,
especially for the tensile modulus which is more than twice of
75. that
of neat PLA (35 GPa).
Fuqua and Ulven reported that fiber loading of treated (alkali
and bleached) and untreated flax fiber without compatibilizer
(maleic anhydride grafted polypropylene or MAPP) in PP
compos-
ites caused inferior tensile strength (even compared with pure
PP)
[19]. However, treated fiber loading with compatibilizer
resulted in
favourable tensile strength as depicted in Fig. 16 [19]. Fig. 17
illus-
trated that the continuously increased trend of composite
modulus
can be found in all cases (untreated, bleached and treated) and
reached a maximum value at 65/5/30 (wt.% PP/MAPP/fiber
loading)
[19]. This can be argued that the introduction of alkali treatment
with 5% MAPP in the natural fiber reinforced plastic
composites
helped to improve both tensile strength and Young’s modulus of
the composites compare to those without MAPP.
Liu et al. evaluated the effects of different fiber surface modifi-
76. cations, 2%NaOH, 2 + 5%NaOH (Note that 2 + 5% NaOH
treatment is
a continuation treatment from 2%NaOH process and then soaked
with 5% NaOH) and coupling agent, on jute/polybutylene
succinate
(PBS) bio-composites [20]. The experiment results showed that
surface modifications could remove surface impurities,
increased
surface roughness and reduced diameter of jute fiber, subse-
quently, significantly increased the tensile strength and modulus
of the composites but decreased breaking elongation as depicted
in Figs. 18–20. It was observed that the bio-composites of jute
fi-
bers treated by 2%NaOH, 2 + 5%NaOH or coupling agent,
obviously
had their tensile properties increased when compared to those
un-
treated and yielded an optimum value at fiber content of 20
wt.%.
The results also showed that the strength and stiffness of
compos-
ites were dependent on the types of treatment. In Figs. 21 and
22,
the 100/0/0 referred to w/t% of PP (100%), MAPP (0%) and
fiber loading
77. (0%); while 65/5/30 referred to w/t% of PP (65%), MAPP (5%)
and fiber
loading (30%).
Li et al. [14] studied flax fiber reinforced polyethylene bio-
composites. In the study, flax fibers, containing 58 w/t% of flax
shives
were used to reinforce polyethylene (high-density polyethylene
and
linear low density polyethylene). The composites contained 10
w/t%
of fiber and processed by extrusion and injection moulding.
Five sur-
face modification methods, alkali, silane, potassium
permanganate,
acrylic acid, and sodium chlorite treatments, were employed to
im-
prove the interfacial bonding between fibers and matrix. Fig. 21
0
5
81. a)
kenaf Jute
Fig. 13. Tensile modulus of bio-composites of PP vs. fibre
weight fraction [adapted from 13].
0
10
20
30
40
50
60
30 35 40 45 50
Fiber volume fraction (%)
82. Te
ns
ile
s
tr
en
gt
h
(M
P
a)
Fiber untreated Fiber alkali treated
Fig. 14. Tensile strength of treated and untreated hemp-PLA
composites vs. fibre content [adapted from 18].
H. Ku et al. / Composites: Part B 42 (2011) 856–873 861
(LLDPE) and Fig. 22 (HDPE) showed that the biocomposite
tensile
83. strengths were increased after surface modifications. Among
these
surface modification techniques, acrylic acid was found to be a
rela-
tively good method in enhancing tensile properties of both flax/
HDPE and LLDPE bio-composites [14].
Fuqua and Ulven investigated the different MAPP loading (0, 5
and 10 w/t%) effects on tensile properties of corn chaff fiber
rein-
forced polypropylene composites [19]. They also investigated
the
effect of various treatments, silane z-6011, silane z-6020 and
5 w/t% MAPP, on corn chaff fiber & distilled dried grains
(DDGS)
0
10
20
30
85. us
(G
P
a)
Fiber untreated Fiber alkali treated
Fig. 15. Tensile modulus of treated and untreated hemp-PLA
composites vs. fibre content [adapted from 18].
0
5
10
15
20
25
30
86. 35
100/0/0 85/0/15 80/5/15 70/0/30 65/5/30
Formulation
Te
ns
ile
s
tr
en
gt
h
(M
P
a)
Untreated fiber Bleached fiber Alkaline treated fiber
87. Fig. 16. Effect of coupling agent concentration on tensile
strength of PP composites with 10% w/t coir fibre [adapted from
19].
0
0.2
0.4
0.6
0.8
1
1.2
1.4
100/0/0 85/0/15 80/5/15 70/0/30 65/5/30
Formulation
Y
88. ou
ng
's
m
od
ul
us
(G
P
a)
Untreated fiber Bleached fiber Alkaline treated fiber
Fig. 17. Effect of coupling agent concentration on Young’s
modulus of PP composites with 10 w/t% coir fibre [adapted
from 19].
862 H. Ku et al. / Composites: Part B 42 (2011) 856–873
90. tr
en
gt
h
(M
P
a)
Without treatment 2% NaOH teatment 2%+5%NaOH treatment
Coupling agent treatment
Fig. 18. Effect of surface modification on tensile strength of
PBS/jute bio-composites with different fibre loading [adapted
from 20].
0
0.5
1
1.5
91. 2
2.5
0 5 10 15 20 25 30
Fiber content (wt%)
Te
ns
ile
m
od
ul
us
(G
P
a)
Without treatment 2% NaOH teatment 2%+5%NaOH treatment
92. Coupling agent treatment
Fig. 19. Effect of surface modification on tensile modulus of
PBS/jute bio-composites with different fibre loading [adapted
from 20].
0
1
2
3
4
5
6
7
0 5 10 15 20 25 30
Fiber content (wt %)
93. B
re
ak
in
g
el
en
ga
tio
n
(%
)
Without treatment 2% NaOH teatment 2%+5%NaOH treatment
Coupling agent treatment
Fig. 20. Effect of surface modification on breaking elongation
of PBS/jute bio-composites with different fibre loading [adapted
from 20].
94. H. Ku et al. / Composites: Part B 42 (2011) 856–873 863
reinforced polypropylene composites [19]. It was found that 5
w/t%
MAPP yielded the optimum value for the composites in term of
tensile strength and modulus as shown in Figs. 23 and 24
respec-
tively [19]. The strength reduction observed with high MAPP
12.8
13
13.2
13.4
13.6
13.8
14
14.2
14.4
LL
D
111. 0 wt% MAPP
5 wt% MAPP
10 wt% MAPP
Fig. 23. Effects of MAPP loading on tensile strength of corn
chaff fibre reinforced PP composites [adapted from 19].
864 H. Ku et al. / Composites: Part B 42 (2011) 856–873
loading was caused by the interaction between the
compatibilizer
(MAPP) and the fiber/matrix system. The anhydride units of
MAPP
maintain loop confirmations within the composite systems,
since
they all can act with equal probability with the cellulose in the
corn fibers. Coupled with MAPP’s low average molecular
weight,
the interaction between the PP matrix and MAPP becomes domi-
nated principally by Van der Waals forces; since chain
entangle-
ment of PP and MAPP is virtually impossible. MAPP that is not
utilizes for fiber/matrix adhesion and is therefore mechanically
harmful to the composites, which leads credence to the
significant
performance variation between 5 and 10 w/t% loadings.
112. However,
through the use of 5 w/t% MAPP, it was found that the tensile
prop-
erties of the composites increase, especially tensile strength
com-
pared to neat resin and those untreated.
Sain et al. investigated the effect of a low-molecular weight
MAPP on tensile properties of polypropylene reinforced with
the
varieties of natural fibers such as old newsprint, kraft pulp and
hemp [20]. Figs. 25 and 26 showed that the optimum level of
the
0
0.2
0.4
0.6
0.8
114. us
(G
P
a)
0 wt% MAPP
5 wt% MAPP
10 wt% MAPP
Fig. 24. Effects of MAPP loading on tensile modulus of corn
chaff fibre reinforced PP composites [adapted from 19].
0
10
20
30
40
115. 50
60
0 1 2 3 4 5
Coupling Agent, wt%
Te
ns
ile
s
tr
en
gt
h
(M
P
a)
116. Tensile strength (MPa)
Fig. 25. Tensile strength of MAPP loaded old newsprint-filled
PP composites [adapted from 20].
3
3.05
3.1
3.15
3.2
3.25
3.3
43210
Coupling Agent, wt%
Te
117. ns
ile
m
od
ul
us
(G
P
a)
Tensile modulus (GPa)
Fig. 26. Tensile modulus of MAPP loaded old newsprint-filled
PP composites [adapted from 20].
H. Ku et al. / Composites: Part B 42 (2011) 856–873 865
coupling agent (MAPP) by weight of the old newsprint-filled PP
composites was 4% for tensile strength and 1.5% for tensile
modu-
lus respectively [20].
118. Herrero-Franco and Valadez-Gonzalez studied the tensile
behaviour of HDPE reinforced with continuous henequen fibers,
which were treated by the optimum concentration (0.015 wt.%)
of silane coupling agent concentration [21]. The results
indicated
that silane increased tensile strength of the composite. It was
no-
ticed, however, that none of the fiber–matrix interface improve-
ments had any significant effect on the value of Young’s
modulus
of continuous henequen fiber reinforced HDPE composites [21].
Another important factor that significantly influences the
properties and interfacial characteristics of the composites is
pro-
cessing techniques and parameters used. Common methods for
manufacturing natural fiber reinforced thermoplastic composites
are extrusion-injection moulding and compression moulding.
Tungjitpornkull and Sombatsompop researched on the
difference
in the tensile properties of E-glass fiber (GF) reinforced
0
120. m
od
ul
us
(G
P
a)
Compression molding Twin screw extrusion
Fig. 27. Tensile modulus of glass fibre reinforced WPVC
composites manufactured by twin screw extrusion and
compression moulding processes [adapted from 22].
866 H. Ku et al. / Composites: Part B 42 (2011) 856–873
wood/PVC (WPVC) composites, manufactured by twin screw
extrusion and compression moulding processes respectively
[22].
The experimental results suggested that the GF/WPVC
composites
produced from compression moulding gave better tensile
modulus
121. than those from their counterparts as depicted in Fig. 27. The
shear
stress in compression moulding was lower than that in twin
screw
extrusion, as a result there was less thermal degradation of PVC
molecules and less breakage of glass fiber, resulting in longer
fiber
length in the composites manufactured by compression
moulding.
The composite manufactured by compression moulding would
have higher specific density, which resulted in less void and air
and was then stronger than its counterpart [22].
The study by Siaotong et al. aimed to determine the optimum
val-
ues for fiber content by mass (0%, 12.5% and 25%), extrusion
barrel
zone temperatures (75–110-120–130-140 �C and 75–120-130–
140-150 �C) and extrusion screw speed (110 and 150 rpm) for
the
production of flax fiber reinforced polyethylene (HDPE and
LLDPE)
composites [23]. Response surface methodology was applied as
opti-
mization technique over three response variables: density
122. deviation
(%), tensile strength (MPa) and water absorption (% mass
increase) of
the composites. According to statistical analysis, the optimum
val-
ues that yield the highest tensile strength (17.09 MPa for
LLDPE
composite and 21.70 MPa for HDPE composite) were: fiber
content
of 6.25%, barrel zone temperatures of 75–116-126–136-146 �C
and
screw speed of 118 rpm for LLDPE composites, and fiber
content of
5%, barrel zone temperatures of 75–118-128–138-148 �C and
screw
speed of 128 rpm for HDPE composites. The optimum values of
tem-
peratures (T) were closer to the higher levels (75–120-130–140-
150 �C) because lower temperatures result in inconsistent melt
of
resin that can lead to non-uniform dispersion of the fibers in the
composites and eventually lower the tensile strength. The
optimum
values of screw speed were closer to the lower level (110 rpm).
This
123. was because the higher screw speed led to shorter residence
time,
non-uniform dispersion of fibers, high porosity, and
consequently,
lowers tensile strength. However, the unexpected result was the
very low optimum level of the fiber content. Theoretically, an
in-
crease of flax fibers should improve the mechanical properties
of
the composites, yet, the results of tensile strength negated this
[23].
Li et al. determined the appropriate value of injection tempera-
ture and pressure for flax fiber reinforced high-density
polyethyl-
ene bio-composites. The results showed that higher fiber
content
in composites led to higher mechanical strength [24]. Injection
temperature of lower than 192 �C was recommended for better
composite quality because at higher temperature, fiber degrada-
tion (fiber degradation temperature � 200 �C) might have oc-
curred, therefore, lead to inferior tensile properties. However,
the
injection temperature should not be lower than 160 �C in order
to ensure adequate melting of matrix. In comparison with
124. injection
temperature, the influence of injection pressure was not
obvious.
However, higher injection pressure is preferred to obtain better
composite tensile properties [24].
The optimum pressure was determined for the natural fibre mat
(hemp and kenaf) reinforced acrylic resin manufactured by
high-
tech vacuum compression process. Fig. 28 showed that the
maxi-
mum pressure for the composites was at 60 bars. Above this
value,
there was a decrease in tensile properties of the composites due
to
the damage of the fiber structure. The advantages of using
vacuum
technology are to allow a reduction of the press time to a
minimum
without decreasing the performance of the cured materials. In
addition, the work conditions were significantly improved when
the vacuum chamber process was used. [25].
Khondker et al. studied the processing conditions of unidirec-
tional jute yarn reinforced polypropylene composites fabricated
125. by film stacking methods [26]. From optical micrographs
obtained,
they suggested that there must be an optimum processing
temper-
ature for which this composite might perform better in tensile
properties. According to the optical microscopy results, they
showed that the composites moulded at a temperature of 160 �C
for 15 min and under 2.0 MPa moulding pressure, would have
the PP matrix films fused and the PP melted completely and
pene-
trated into the fiber bundles. This temperature was considered
favourably ideal for the processing of composites that used
ligno-
cellulosic fibers as reinforcement, as most lignocellulosic fibers
cannot withstand processing temperatures higher than 175 �C
for
longer duration, and hence limiting their ability to be used with
some thermoplastic resins [26].
The effect of the melting-mixing technique parameters on the
tensile properties of sisal fiber reinforced polypropylene
compos-
ites were optimised by varying the 29 through 32, mixing time
of 10 min, rotor speed of 50 rpm and a mixing temperature of
170 �C were found to be the optimum mixing conditions. For
126. mix-
ing times (Figs. 29 and 30), below the optimum value, the
tensile
strength and Young’s modulus were low because of ineffective
mixing and poor dispersion of the fiber in PP matrix. As the
mixing
time was increased, melting of PP resin became extensive and
re-
sulted in better fiber distribution into the matrix. When mixing
time was more than 10 min, fiber breakage and degradation
would
happen, leading to a decrease in tensile properties. For mixing
tem-
peratures (Fig. 31), the performance of short fiber composites
was
controlled directly by fiber aspect ratio, quality of dispersion
and
0
1000
2000
128. us
(M
P
a)
MD CD
Fig. 28. Tensile modulus of natural fiber mat (hemp and kenaf)
reinforced acrylic composites in machine direction (MD) and
cross direction (CD) under varying pressures
[adapted from 25].
28
29
30
31
32
33
129. 34
35
36
37
0 2 4 6 8 10 12 14
Time (min)
Te
ns
ile
s
tr
en
gt
h
(M
130. P
a)
Fig. 29. Tensile strength of melting mixing of PP/sisal
composites with varying mixing times; fibre content 30%, fibre
length 10 mm [adapted from 27].
28
29
30
31
32
33
34
35
36
131. 37
38
0 2 4 6 8 10 12 14
Time (min)
Y
ou
ng
's
m
od
ul
us
(M
P
a)
132. Fig. 30. Tensile modulus of melting mixing of PP/sisal
composites with varying mixing times; fibre content 30%, fibre
length 10 mm [adapted from 27].
H. Ku et al. / Composites: Part B 42 (2011) 856–873 867
interface between fiber and polymer. Below the optimum value,
viscosity as well as shear stress generated in the mixture was
very
high, resulting in the break down of fibers to shorter lengths
during
mixing, leading to a lower tensile strength of the composites.
On
the other hand, if mixing temperature was above the optimum,
the thermal degradation of fibers would occur, leading to the
de-
crease of tensile properties. For mixing speeds (Fig. 32), low
tensile
strength was observed at speeds lower than the optimum value
0
5
134. gt
h
(M
P
a)
Fig. 31. Tensile strength of melting mixing of PP/sisal
composites with varying mixing temperatures; fibre content
30%, fibre length 10 mm [adapted from 27].
25
27
29
31
33
35
135. 37
39
30 35 40 45 50 55 60
Rotor speed (rpm)
Te
ns
ile
s
tr
en
gt
h
(M
P
a)
136. Fig. 32. Tensile strength of melting mixing of PP/sisal
composites with varying rotor speeds; fibre content 30%, fibre
length 10 mm [adapted from 27].
868 H. Ku et al. / Composites: Part B 42 (2011) 856–873
due to poor dispersion of fibers in molten PP matrix. Above the
optimum rotor speed, there was a reduction in strength because
of fiber breakage at high rotor speed [27].
3. Mathematical modelling
Facca et al. exploited a micromechanical model which was a
semi-empirical modification of the rule of mixtures (ROM)
strength Eq. (10):
r1U ¼ rFU 1 �
lC
2l
� �
V F þ r�Mð1 � V FÞ; l P lC ð1Þ
The modified equation for cylindrical fibers was
r1U ¼ asiV F
l
137. d
þ r�Mð1 � V FÞ; l 6 lC ð2Þ
The modified equation for rectangular fibers was
r1U ¼ asiV F
l
2
� �
W þ T
WT
� �
þ r�Mð1 � V FÞ; l 6 lC ð3Þ
where r1U, a, si, r�M , l, lC, VF, d, W, T are composite tensile
strength,
the clustering parameter, interfacial shear strength, maximum
stress evaluated at the peak composite strength, fiber length,
criti-
cal fiber length, fiber volume fraction, cylindrical fiber
diameter,
rectangular fiber width, rectangular fiber thickness,
138. respectively.
All of the above-mentioned parameters are available from liter-
ature to predict the tensile strength of HDPE reinforced with a
vari-
ety of natural fibers (hemp, hardwood flour and rice hulls) and
synthetic (E-glass) fibers [10].
Note that, the direction of short fiber is assumed to be perfectly
aligned and fiber curvature is negligible. Also, experimental ap-
proaches are required to determine the interfacial shear strength
(si) of the fiber; either fiber pullout or fragmentation test can be
used. Figs. 33–37 showed the predicted and experimental tensile
strength of different natural fiber reinforced HDPE composites
[10]. It was found that for most cases the tensile strength of the
predicted and experimental results were at par. It can be argued
that Eqs. (1)–(3) gave a good prediction of the experimental
results
except those shown in Fig. 37, where, the experimental tensile
strength of HDPE composites reinforced with rice hulls fibers
ini-
tially increased to a maximum value of 24.88 MPa at 5 vol.% of
rice
hulls fiber; it then gradually dropped to a minimum value of
17.11 MPa at 40 vol.% of filler. On the other hand, the
predicted
139. tensile strength of the composites initially decreased to a mini-
mum value of 21.78 MPa at 5 vol.% of rice hulls fiber; it then
grad-
ually increased to a maximum value of 28.78 MPa at 25 vol.%
of
filler before dropping back to 24.11 MPa at 40 vol.% of filler
[10].
Facca et al. also found that the increase by weight of natural
short fibers like hemp, hardwood, rice hulls in high-density
poly-
ethylene manufactured by twin-screw brabender mixer com-
pounding and compression moulding, increased the tensile
modulus of all composites [11]. Again, in order to reduce cost
0
5
10
15
141. gt
h
(M
P
a)
Exp. composite tensile strength Predicted composite tensile
strength
Fig. 33. Predicted and experimental tensile strengths of HDPE
composite reinforced with hemp fibers between fiber loadings
of 10–60 wt.% [adapted from 10].
0
10
20
30
40
142. 50
60
0 0.05 0.1 0.15 0.2 0.25 0.3
Volume fraction of E-glass fibers
Te
ns
ile
s
tr
en
gt
h
(M
P
a)
143. Experimental composite tensile strength Predicted composite
tensile strength
Fig. 34. Predicted and experimental tensile strengths of HDPE
composites reinforced with E-glass fibers between fiber
loadings of 10–60 wt.% [adapted from 10].
0
5
10
15
20
25
0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4
Volume fraction of 20-mesh hardwood fibers
Te
ns
144. ile
s
tr
en
gt
h
(M
P
a)
Experimental composite tensile strength Predicted composite
tensile strength
Fig. 35. Predicted and experimental tensile strengths of HDPE
composites reinforced with 20-mesh hardwood fibers between
fiber loadings of 10–60 wt.% [adapted from 10].
H. Ku et al. / Composites: Part B 42 (2011) 856–873 869
and time consuming experiments, the experimental results of the
tensile modulus of the composites were compared with the theo-
145. retical values obtained from various mathematical models
shown
in Eqs. (4)–(9):
(1) Rule of mixture (ROM) [11]:
E ¼ EF V F þ EM V M ð4Þ
where EF, VF, EM and VM are the moduli and volume fractions
of the
fiber and matrix respectively.
(2) Inverse/transverse rule of mixtures (IROM) [11]:
E ¼
EF EM
V M EF þ V F EM
ð5Þ
where EF, VF, EM and VM are the moduli and volume fractions
of the
fiber and matrix respectively.
0
5
146. 10
15
20
25
30
35
0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4
Volume fraction of 40-mesh hardwood fibers
Te
ns
ile
s
tr
en
147. gt
h
(M
P
a)
Experimental composite tensile strength Predicted composite
tensile strength
Fig. 36. Predicted and experimental tensile strengths of HDPE
composite reinforced with 40-mesh hardwood fibers between
fiber loadings of 10–60 wt.% [adapted from 10].
0
5
10
15
20
148. 25
30
35
0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4
Volume fraction of rice hulls fibers
Te
ns
il
st
re
ng
th
(M
P
a)
149. Experimental composite tensile strength Predicted composite
tensile strength
Fig. 37. Predicted and experimental tensile strength of HDPE
composites reinforced with rice hulls fibers between fiber
loadings of 10–60 wt.% [adapted from 10].
870 H. Ku et al. / Composites: Part B 42 (2011) 856–873
(3) Halpin–Tsai Eq. (11):
E ¼ EM
1 þ ngV F
1 � gV F
� �
ð6Þ
In Eq. (6) the parameter g is given as:
g ¼
ðEF=EMÞ� 1
ðEF=EMÞþ n
ð7Þ
where n in Eqs. 6 and 7 is a shape fitting parameter to fit
Halpin–
Tsai equation to experimental data. The significance of the
150. parame-
ter n is that it takes into consideration the packing arrangement
and
the geometry of the reinforcing fibers.
A variety of empirical equations for n are available in the liter-
ature, and they depend on the shape of the particle and on the
modulus that is being predicted. If the tensile modulus in the
prin-
cipal fiber direction is desired, and the fibers are rectangular or
cir-
cular in shape, then n is given by the following equations:
n ¼ 2
L
T
� �
or n ¼ 2
L
D
� �
ð8Þ
151. where L is the length of a fiber in the one-direction and T or D
is the
thickness or diameter of the fiber.
(4) Shear-lag theory:
E ¼ EF 1 �
tanhðgL2Þ
ðgL2Þ
!
V F þ EM V M ð9Þ
the parameter g for shear-lag analysis is available on the
literature
[10].
E ¼
3
8
E1 þ
5
8
152. E2 ð10Þ
where E is the elastic modulus of the composite. E1 and E2 are
the
elastic moduli of randomly oriented fiber reinforced composites
gi-
ven by Halpin–Tsai equations (Eq. (12)) [14]:
Ei ¼ EM
1 þ nigiV F
1 � gi V F
� �
; gi ¼
ðEF=EMÞ� 1
ðEF=EMÞþ ni
; ð11Þ
where ni = 2(lf/df) for i = 1 or ni = 0.5 for i = 2
Figs. 38–42 showed the Young’s modulus of natural fibers
(hemp, hardwood, rice hulls and E-glass) reinforced high-
density
polyethylene composites containing different types of natural fi-
bers at different volume fraction of the fibers. It was found that,
Halpin–Tsai model was the most accurate amongst others to
153. pre-
dict tensile modulus of natural fiber reinforced thermoplastics
used in the study made by Facca et al. [11].
Lee et al. found that the tensile moduli of the kenaf or jute rein-
forced PP composites increased with increasing fiber contents
up
to 40% fiber weight fraction. Furthermore, the study employed
Tsai
and Pagano’s model (Eq. (11)) in predicting the tensile modulus
of
randomly oriented long-discontinued fiber reinforced
composites.
It was found that the model predictions agreed well with experi-
mental results for the volume fraction of less than 30–40% by
weight of kenaf and jute respectively, where the void content
were
not high as illustrated in Figs. 43 and 44 respectively [13].
0
5
154. 10
15
20
25
0 0.05 0.1 0.15 0.2 0.25 0.3
Volume fraction of E-glass fibers
Y
ou
ng
's
m
od
ul
us
(G
155. P
a)
Experimental Tensile Strength (MPa) Rule of Mixture
Inverse Rule of Mixture Halpin Tsai
Nairn shear-lag Mendels et al.
Fig. 38. Young’s modulus of HDPE composites containing E-
glass fibers [adapted from 11].
0
2
4
6
8
10
12
156. 14
16
0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4
Volume fraction of hardwood A fibers
Y
ou
ng
's
m
od
ul
us
(G
P
a)
Experimental Tensile Strength (MPa) Rule of Mixture
157. Inverse Rule of Mixture Halpin Tsai
Nairn shear-lag Mendels et al.
Fig. 39. Young’s modulus of HDPE composites containing
hardwood A [adapted from 11].
0
5
10
15
20
25
30
0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4
Volume fraction of hemp fibers
159. fibers [adapted from 11].
H. Ku et al. / Composites: Part B 42 (2011) 856–873 871
4. Discussions and conclusions
The scientific world is facing a serious problem of developing
new and advanced technologies and methods to treat solid
wastes,
particularly non-naturally-reversible polymers. The processes to
decompose those wastes are actually not cost-effective and will
subsequently produce harmful chemicals. Owing to the above
ground, reinforcing polymers with natural fibers is the way to
go.
In this paper, most of the natural fibers mentioned were
plant-based but it should be noted that animal fibers like cocoon
0
2
4
6
8
10
160. 12
14
16
0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45
Volume fraction of hardwood B fibers
Y
ou
ng
's
m
od
ul
us
(G
P
a)
Experimental Tensile Strength (MPa) Rule of Mixture
161. Inverse Rule of Mixture Halpin Tsai
Nairn shear-lag Mendels et al.
Fig. 41. Young’s modulus of HDPE composites containing
hardwood B [adapted from 11].
0
2
4
6
8
10
12
0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.5
Volume fraction of rice hulls
163. hulls [adapted from 11].
0
500
1000
1500
2000
2500
3000
0 10 20 30 40 50 60 70
Fiber weight fraction (%)
Te
ns
ile
m
164. od
ul
us
(M
P
a)
kenaf Prediction
Fig. 43. Predicted and experimental result of tensile modulus of
kenaf reinforced PP composites [adapted from 13].
872 H. Ku et al. / Composites: Part B 42 (2011) 856–873
silkworm silk, chicken feather and spider silk have also been
used
and the trend should go on. Those fibers, both animal- and
plant-based have provided useful solutions for new materials
development, in the field of material science and engineering.
Natural fibers are indeed renewable resources that can be grown
and made within a short period of time, in which the supply can
be unlimited as compared with traditional glass and carbon
fibers
for making advanced composites. However, for some recyclable
165. polymers, their overall energy consumption during collecting,
recycling, refining and remoulding processes have to be
considered
to ensure the damage of the natural cycle would be kept as
minimal.
On top of it, Natural fibers are low cost, recyclable, low density
and eco-friendly material. Their tensile properties are very good
0
0.2
0.4
0.6
0.8
1
1.2
166. 1.4
1.6
1.8
0 10 20 30 40 50 60 70
Fiber weight fraction (%)
Te
ns
ile
m
od
ul
us
(G
P
a)
167. Jute Prediction
Fig. 44. Predicted and experimental result of tensile modulus of
jute reinforced PP composites [adapted from 13].
H. Ku et al. / Composites: Part B 42 (2011) 856–873 873
and can be used to replace the conventional fibers such as glass,
carbon in reinforcing plastic materials. A major drawback of
using
natural fibers as reinforcement in plastics is the incompatibility,
resulting in poor adhesion between natural fibers and matrix
resins,
subsequently lead to low tensile properties. In order to improve
fi-
ber–matrix interfacial bonding and enhance tensile properties of
the composites, novel processing techniques, chemical and
physical
modification methods are developed. Also, it is obviously clear
that
the strength and stiffness of the natural fiber polymer
composites
is strongly dependent on fiber loading. The tensile strength and
modulus increase with increasing fiber weight ratio up to a
certain
amount. If the fiber weight ratio increases below optimum
168. value,
load is distributed to more fibers, which are well bonded with
resin
matrix resulting in better tensile properties. Further increment
in fi-
ber weight ratio has resulted in decreased tensile strength as de-
scribed in the main text. Mathematical models were also found
to
be an effective tool to predict the tensile properties of natural
fiber
reinforced composites.
Finally, it can be found that the main weakness to predict the
tensile properties of plant-based natural fiber composites by
mod-
elling was giving too optimistic values like results in Figs. 33–
37.
The modelling has to be improved to allow improvements in the
prediction of tensile properties of composites reinforced with
both
plant- and animal-based fibers.
References
[1] Khoathane MC, Vorster OC, Sadiku ER. Hemp fiber-
169. reinforced 1-pentene/
polypropylene copolymer: the effect of fiber loading on the
mechanical and
thermal characteristics of the composites. J Reinf Plast Compos
2008;27:1533–44.
[2] Groover MP. Fundamental of modern manufacturing. 2nd ed.
111 River Street,
Hoboken (NJ): John Wiley & Sons, Inc.; 2004.
[3] Malkapuram R, Kumar V, Yuvraj SN. Recent development
in natural fibre
reinforced polypropylene composites. J Reinf Plast Compos
2008;28:1169–89.
[4] Nabi Saheb D, Jog JP. Natural fiber polymer composites: a
review. Adv Polym
Technol 1999;18:351–63.
[5] Li X, Tabil LG, Panigrahi S, Crerar WJ. The influence of
fiber content on
properties of injection molded flax fiber-HDPE biocomposites.
Can Biosyst Eng
2009;08–148:1–10.
170. [6] Wambua P, Ivens J, Verpoest I. Natural fibres: can they
replace glass in fibre
reinforced plastics. Compos Sci Technol 2003;63:1259–64.
[7] Ahmad I, Baharum A, Abdullah I. Effect of extrusion rate
and fiber loading on
mechanical properties of Twaron fiber-thermoplastic natural
rubber (TPNR)
composites. J Reinf Plast Compos 2006;25:957–65.
[8] Holbery J, Houston D. Natural-fiber-reinforced polymer
composites in
automotive applications. JOM 2006;58(11):80–6.
[9] Hajnalka H, Racz I, Anandjiwala RD. Development of
HEMP fibre reinforced
polypropylene composites. J Thermoplast Compos Mater
2008;21:165–74.
[10] Facca AG, Kortschot MT, Yan N. Predicting the tensile
strength of natural fibre
reinforced thermoplastics. Compos Sci Technol 2007;67:2454–
66.
[11] Facca AG, Kortschot MT, Yan N. Predicting the elastic
modulus of natural fiber
171. reinforced thermoplastics. Compos: Part A: Appl Sci Manuf
2007;37:
1660–71.
[12] Ma X, Yu J, Kennedy JF. Studies on the propertied of
natural fibres-reinforced
thermoplastic starch composites. Carbohydr Polym 2005;62:19–
24.
[13] Lee BH, Kim HJ, Yu WR. Fabrication of long and
discontinuous natural fibre
reinforced polypropylene biocomposites and their mechanical
properties.
Fiber Polym 2009;10:83–90.
[14] Li X, Panigrahi S, Tabil LG. A study on flax fiber-
reinforced polyethylene
biocomposites. Appl Eng Agr 2009;25:525–31.
[15] Panigrahy BS, Rana A, Chang P, Panigrahi S. Overview of
flax fibre reinforced
thermoplastic composites. Can Biosyst Eng J 2006;06–165:1–
12.
[16] Lopez Manchado MA, Arroya M, Biagiotti J, Kenny JM.
172. Enhancement of
mechanical properties and interfacial adhesion of
PP/EPDM/Flax Fibre
Composites using maleic anhydride as a compatibilizer. J Appl
Polym Sci
2003; 90: 2170–2178.
[17] Santos EF, Mauler RS, Nachtigall SMB. Effectiveness of
maleated- and
salinized-PP for coir fiber-filled composites. J Reinf Plast
Compos
2009;28:2119–29.
[18] Hu R, Lim JK. Fabrication and mechanical properties of
completely
biodegradable hemp fibre reinforced polylactic acid composites.
J Compos
Mater 2007;41:1655–69.
[19] Fuqua MA, Ulven CA. Preparation and characterization of
polypropylene
composites reinforced with modified lignocellulosic corn fiber.
The Canadian
Society for Bioengineering; 2008 [Paper no: 084364, p.].