This presentation provides basics of self healing polymers along with all the different types of polymers and mechanisms involved including a focus on new extrinsic and intrinsic technologies.It also discusses the applications of self healing polymers
Self-healing materials are smart materials that can intrinsically repair damage leading to longer lifetimes, reduction of inefficiency caused by degradation and material failure.
Applications include shock absorbing materials, paints and anti-corrosion coatings and more recently, conductive self-healing materials for circuits and electronics.
It is just an literature survey presentation about self healing Polymer technology and its classification and different types of method to implement in a real word in future..
The concept of an autonomic self-healing material, where initiation of repair is integral to the material, is now being considered for engineering applications. This bio-inspired concept offers the designer an ability to incorporate secondary functional materials capable of counteracting service degradation whilst still achieving the primary, usually structural, requirement. Most materials in nature are themselves self-healing composite materials. This paper reviews the various self-healing technologies currently being developed for fiber reinforced polymeric composite materials, most of which are bioinspired; inspired by observation of nature. The most recent self-healing work has attempted to mimic natural healing using more detailed study of natural processes. A perspective on current and future self-healing approaches using this biomimetic technique is offered. The intention is to stimulate debate and reinforce the importance of a multidisciplinary approach in this exciting field.
This paper presents a brief discussion of the types and characteristics of self-healing coating systems. Three main structural schemes used in these systems are explained, followed by a review of the synthesis, characterization, and applications of poly(dicyclopentadiene)/Grubbs catalyst system as a case study. The ring-opening metathesis polymerization of dicyclopentadiene in this system is explored, then, methods for chemical and mechanical characterization of the resulting polymer are identified. Finally, advantages of utilizing such a system as well as several potential applications are highlighted.
Self-healing materials are smart materials that can intrinsically repair damage leading to longer lifetimes, reduction of inefficiency caused by degradation and material failure.
Applications include shock absorbing materials, paints and anti-corrosion coatings and more recently, conductive self-healing materials for circuits and electronics.
It is just an literature survey presentation about self healing Polymer technology and its classification and different types of method to implement in a real word in future..
The concept of an autonomic self-healing material, where initiation of repair is integral to the material, is now being considered for engineering applications. This bio-inspired concept offers the designer an ability to incorporate secondary functional materials capable of counteracting service degradation whilst still achieving the primary, usually structural, requirement. Most materials in nature are themselves self-healing composite materials. This paper reviews the various self-healing technologies currently being developed for fiber reinforced polymeric composite materials, most of which are bioinspired; inspired by observation of nature. The most recent self-healing work has attempted to mimic natural healing using more detailed study of natural processes. A perspective on current and future self-healing approaches using this biomimetic technique is offered. The intention is to stimulate debate and reinforce the importance of a multidisciplinary approach in this exciting field.
This paper presents a brief discussion of the types and characteristics of self-healing coating systems. Three main structural schemes used in these systems are explained, followed by a review of the synthesis, characterization, and applications of poly(dicyclopentadiene)/Grubbs catalyst system as a case study. The ring-opening metathesis polymerization of dicyclopentadiene in this system is explored, then, methods for chemical and mechanical characterization of the resulting polymer are identified. Finally, advantages of utilizing such a system as well as several potential applications are highlighted.
In this PPT you know about the SELF HEALING technology in spacecrafts
This technology is still under research in NASA.
This technology can be also implement on Aircrafts.So it is very simple concept it includes some basic knowledge about Composites materials and its properties.
Self-healing polymers are smart materials that have the capability to repair themselves when they are damaged without the need for detection or repair by manual intervention of any kind.
This review explains some applications of nanocomposites , further, its covers the classification of nanocomposite and outlooks regarding this materials .
It is described about polymer/clay nanocomposites which can be abbreviated to PCNC, their preparation methods, properties and relevances, important types of polymers employed in the preparation of PCNC, montmorillonite crystal structures,
Introduction to adhesive and adhesion, this powerpoint slide will explain you about what is an adhesive, advantage and disadvantage of joining using adhesive. In addition, you will understand the basics of adhesive theory i.e. the requirement of a good bond, good joint design, types of adhesives.
This presentation dives into the deep realms of nano-chemistry starting from the very basics to a sufficient advanced level. Nano-chemistry has always been a very intriguing topic for most of us as we see it in movies more than frequently. If not, we at least hear some explanation about a curious event that relates directly to nano-chemistry.
Diving into the depths of those explanations related to nano-chemistry and revealing the actual facts about nano-chemistry and its related topics. We have formulated this presentation to become a crucial source of information regarding nano-chemistry and its other related terms.
It is also a study material for Basics of Chemistry subject taught during the 1st or 2nd semesters during B.E. / B.Tech degree courses.
he study aims at highlighting the importance of an effective approach to psychotherapy when working with low-income clients. In addition, changes in the United States demographics require that practicing psychologists acknowledge the importance of class and culture in therapy. Kim and Cardemil based the research on their experience with depression prevention programs designed for low-income mothers of Hispanic origins. Their Family Coping Skills Program incorporates the patient’s social class and focuses on prevention rather than treatment. The article provides several recommendations, such as community psychology incorporation, as well as open acknowledgment of differences between therapists and clients. Kim and Cardemil state that modern psychotherapy must alleviate social barriers and become more comprehensive in respect to issues of different classes and backgrounds.
The article discusses a topical issue of inclusive psychotherapy and provides an array of instruments, which can be used to respond to the clients’ needs. It is vital to consider an individual’s background, which includes both culture and social class when designing the treatment program. Kim and Cardemil make a valuable reference to modern demographics as an attempt to draw the community’s attention to the importance of comprehensive psychotherapy. The provided list of possible ways of managing differences may serve as a valuable reference for therapists.
From a counselor’s point of view, this study provides valuable insight regarding difference managing and inclusiveness.
Cook, J.A., & Mueser, K.T. (2016). Is recovery possible outside the financial mainstream? Psychiatric Rehabilitation Journal, 39(4), 295-298. Web.
Cook and Mueser examine the connection between poor mental health and unfortunate financial situation. The research states that poverty can both cause and be a consequence of mental issues. This article refers to a Swedish study, in which participants with poor mental health received financial support every month and demonstrated reduced levels of anxiety and depression. At the same time, the second group did not receive any financial support and showed no improvement in their condition. Cook and Mueser cite the original study’s authors saying that additional sums allowed people to partake in a broader range of social interactions, thus improving some aspects of their mental health. This article suggests several steps to improve the public’s overall mental health by ensuring access to housing, education, and healthcare.
The way poverty and mental health are related presents various research opportunities. Cook and Mueser discuss this issue at length and provide a valuable reference to a practical study. In addition, the authors make a valid point regarding poverty’s role as both a cause and a consequence of poor mental health. Swedish research, to which the present article refers, serves as another case in point.
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In this PPT you know about the SELF HEALING technology in spacecrafts
This technology is still under research in NASA.
This technology can be also implement on Aircrafts.So it is very simple concept it includes some basic knowledge about Composites materials and its properties.
Self-healing polymers are smart materials that have the capability to repair themselves when they are damaged without the need for detection or repair by manual intervention of any kind.
This review explains some applications of nanocomposites , further, its covers the classification of nanocomposite and outlooks regarding this materials .
It is described about polymer/clay nanocomposites which can be abbreviated to PCNC, their preparation methods, properties and relevances, important types of polymers employed in the preparation of PCNC, montmorillonite crystal structures,
Introduction to adhesive and adhesion, this powerpoint slide will explain you about what is an adhesive, advantage and disadvantage of joining using adhesive. In addition, you will understand the basics of adhesive theory i.e. the requirement of a good bond, good joint design, types of adhesives.
This presentation dives into the deep realms of nano-chemistry starting from the very basics to a sufficient advanced level. Nano-chemistry has always been a very intriguing topic for most of us as we see it in movies more than frequently. If not, we at least hear some explanation about a curious event that relates directly to nano-chemistry.
Diving into the depths of those explanations related to nano-chemistry and revealing the actual facts about nano-chemistry and its related topics. We have formulated this presentation to become a crucial source of information regarding nano-chemistry and its other related terms.
It is also a study material for Basics of Chemistry subject taught during the 1st or 2nd semesters during B.E. / B.Tech degree courses.
he study aims at highlighting the importance of an effective approach to psychotherapy when working with low-income clients. In addition, changes in the United States demographics require that practicing psychologists acknowledge the importance of class and culture in therapy. Kim and Cardemil based the research on their experience with depression prevention programs designed for low-income mothers of Hispanic origins. Their Family Coping Skills Program incorporates the patient’s social class and focuses on prevention rather than treatment. The article provides several recommendations, such as community psychology incorporation, as well as open acknowledgment of differences between therapists and clients. Kim and Cardemil state that modern psychotherapy must alleviate social barriers and become more comprehensive in respect to issues of different classes and backgrounds.
The article discusses a topical issue of inclusive psychotherapy and provides an array of instruments, which can be used to respond to the clients’ needs. It is vital to consider an individual’s background, which includes both culture and social class when designing the treatment program. Kim and Cardemil make a valuable reference to modern demographics as an attempt to draw the community’s attention to the importance of comprehensive psychotherapy. The provided list of possible ways of managing differences may serve as a valuable reference for therapists.
From a counselor’s point of view, this study provides valuable insight regarding difference managing and inclusiveness.
Cook, J.A., & Mueser, K.T. (2016). Is recovery possible outside the financial mainstream? Psychiatric Rehabilitation Journal, 39(4), 295-298. Web.
Cook and Mueser examine the connection between poor mental health and unfortunate financial situation. The research states that poverty can both cause and be a consequence of mental issues. This article refers to a Swedish study, in which participants with poor mental health received financial support every month and demonstrated reduced levels of anxiety and depression. At the same time, the second group did not receive any financial support and showed no improvement in their condition. Cook and Mueser cite the original study’s authors saying that additional sums allowed people to partake in a broader range of social interactions, thus improving some aspects of their mental health. This article suggests several steps to improve the public’s overall mental health by ensuring access to housing, education, and healthcare.
The way poverty and mental health are related presents various research opportunities. Cook and Mueser discuss this issue at length and provide a valuable reference to a practical study. In addition, the authors make a valid point regarding poverty’s role as both a cause and a consequence of poor mental health. Swedish research, to which the present article refers, serves as another case in point.
On-Time Delivery!
Get your 100% customized pap
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Application of Plasma Technology for Coated Textileijsrd.com
More than 99% of the visible matter in the universe is in the plasma state. It can be seen in its natural form on earth as lightning or as polar light in the Arctic and Antarctic. Plasma was first discovered by Irving Langmuir in 1928. Plasma technology is based on a simple physical principle. Matter changes its state when energy is supplied to it: solids become liquid, and liquids become gaseous. If even more energy is supplied to a gas, it is ionized and goes into the energy-rich plasma state, the fourth state of matter.
This presentation describes the technological advancement of today's engineering field.These explains the application of chemistry in adhesives bucky balls and many more nano particles.
This also covers the topic of liquid crystals.
Self-healing dental polymer:mechanism and uses in dentistry.
This presentation discusses briefly the definition ,mechanism and uses of self-healing polymers in dentistry.
Bio Inspired Self-Curing Composite: A Leap into Augmented EnactmentScientific Review SR
Relentless progress has been made on composite materials, their manufacturing processes and their structural design in past few decades. Nevertheless, the approval of composite materials in all engineering disciplines is constrained due to its susceptibility to various kinds of defects during manufacturing stage viz porosity, foreign body inclusion, incorrect fiber volume, bonding defect, fiber misalignment, ply misalignment, incorrect curing cycle, wavy fiber, ply cracking, delamination, fiber microstructural defects etc. Hence there was a requirement of techniques to somehow overcome these defects during the service life of composites being used in various structures and equipment. This promising field of research has made great progress over the past several years, but many procedural encounters are still to be overcome, and there exists a great need for focused research to address several areas of concern. On the other hand, nature has materials that have curing potential and repair strategies ensuring their survival. Sustained development in the field will produce new curing chemistries that possess greater stability, faster kinetics. Tailor-made placement of curing agents is dynamic research subject at the cutting edge of self-curing. New bio-imitative curing agents are closely connected to vascular networks. The purpose of this technical paper is to sort the methodology in line with ongoing research efforts in composites. A perspective on current and future self-curing approaches using this biomimetic technique is offered.
Overview of the fundamental roles in Hydropower generation and the components involved in wider Electrical Engineering.
This paper presents the design and construction of hydroelectric dams from the hydrologist’s survey of the valley before construction, all aspects and involved disciplines, fluid dynamics, structural engineering, generation and mains frequency regulation to the very transmission of power through the network in the United Kingdom.
Author: Robbie Edward Sayers
Collaborators and co editors: Charlie Sims and Connor Healey.
(C) 2024 Robbie E. Sayers
Sachpazis:Terzaghi Bearing Capacity Estimation in simple terms with Calculati...Dr.Costas Sachpazis
Terzaghi's soil bearing capacity theory, developed by Karl Terzaghi, is a fundamental principle in geotechnical engineering used to determine the bearing capacity of shallow foundations. This theory provides a method to calculate the ultimate bearing capacity of soil, which is the maximum load per unit area that the soil can support without undergoing shear failure. The Calculation HTML Code included.
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Courier management system project report.pdfKamal Acharya
It is now-a-days very important for the people to send or receive articles like imported furniture, electronic items, gifts, business goods and the like. People depend vastly on different transport systems which mostly use the manual way of receiving and delivering the articles. There is no way to track the articles till they are received and there is no way to let the customer know what happened in transit, once he booked some articles. In such a situation, we need a system which completely computerizes the cargo activities including time to time tracking of the articles sent. This need is fulfilled by Courier Management System software which is online software for the cargo management people that enables them to receive the goods from a source and send them to a required destination and track their status from time to time.
Automobile Management System Project Report.pdfKamal Acharya
The proposed project is developed to manage the automobile in the automobile dealer company. The main module in this project is login, automobile management, customer management, sales, complaints and reports. The first module is the login. The automobile showroom owner should login to the project for usage. The username and password are verified and if it is correct, next form opens. If the username and password are not correct, it shows the error message.
When a customer search for a automobile, if the automobile is available, they will be taken to a page that shows the details of the automobile including automobile name, automobile ID, quantity, price etc. “Automobile Management System” is useful for maintaining automobiles, customers effectively and hence helps for establishing good relation between customer and automobile organization. It contains various customized modules for effectively maintaining automobiles and stock information accurately and safely.
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Also when the user tries to sale items which are not in stock, the system will prompt the user that the stock is not enough. Customers of this system can search for a automobile; can purchase a automobile easily by selecting fast. On the other hand the stock of automobiles can be maintained perfectly by the automobile shop manager overcoming the drawbacks of existing system.
Final project report on grocery store management system..pdfKamal Acharya
In today’s fast-changing business environment, it’s extremely important to be able to respond to client needs in the most effective and timely manner. If your customers wish to see your business online and have instant access to your products or services.
Online Grocery Store is an e-commerce website, which retails various grocery products. This project allows viewing various products available enables registered users to purchase desired products instantly using Paytm, UPI payment processor (Instant Pay) and also can place order by using Cash on Delivery (Pay Later) option. This project provides an easy access to Administrators and Managers to view orders placed using Pay Later and Instant Pay options.
In order to develop an e-commerce website, a number of Technologies must be studied and understood. These include multi-tiered architecture, server and client-side scripting techniques, implementation technologies, programming language (such as PHP, HTML, CSS, JavaScript) and MySQL relational databases. This is a project with the objective to develop a basic website where a consumer is provided with a shopping cart website and also to know about the technologies used to develop such a website.
This document will discuss each of the underlying technologies to create and implement an e- commerce website.
COLLEGE BUS MANAGEMENT SYSTEM PROJECT REPORT.pdfKamal Acharya
The College Bus Management system is completely developed by Visual Basic .NET Version. The application is connect with most secured database language MS SQL Server. The application is develop by using best combination of front-end and back-end languages. The application is totally design like flat user interface. This flat user interface is more attractive user interface in 2017. The application is gives more important to the system functionality. The application is to manage the student’s details, driver’s details, bus details, bus route details, bus fees details and more. The application has only one unit for admin. The admin can manage the entire application. The admin can login into the application by using username and password of the admin. The application is develop for big and small colleges. It is more user friendly for non-computer person. Even they can easily learn how to manage the application within hours. The application is more secure by the admin. The system will give an effective output for the VB.Net and SQL Server given as input to the system. The compiled java program given as input to the system, after scanning the program will generate different reports. The application generates the report for users. The admin can view and download the report of the data. The application deliver the excel format reports. Because, excel formatted reports is very easy to understand the income and expense of the college bus. This application is mainly develop for windows operating system users. In 2017, 73% of people enterprises are using windows operating system. So the application will easily install for all the windows operating system users. The application-developed size is very low. The application consumes very low space in disk. Therefore, the user can allocate very minimum local disk space for this application.
1. AN INTRODUCTION TO SELF HEALING
POLYMERS
SUBMITTED TO
CHEMICAL ENGINEERING DEPARTMENT
HBTU, KANPUR
PREPARED BY
SHANJUL SHRIVASTAVA
MTECH II -YEAR
2. CONTENTS
1. What are Self Healing Polymers
2. Need & Inspiration
3. Thermodynamics of self-healing ,Entropy Changes and Gibbs Energy
4. Intrinsic systems and examples
5. Extrinsic systems and examples
6. Applications of self healing polymers
7. Problems and Challenges
8. References
3. What are Self Healing
Polymers
Self-healing polymers are
synthetically created ‘smart
materials’ which have the
built-in ability to
automatically repair
damage to themselves
without any external
diagnosis
Ref (4) : fast self-healing of a film of P5 at room temperature
4. Need & Inspiration
Polymers and polymer composites are used in a variety of applications in our
day to day life. However, these materials are susceptible to damage induced
by mechanical, chemical, thermal, UV or a combination of these factors.
Self Healing materials are inspired by
biological systems in which the damage
triggers an autonomic healing response.
THE VISION : if industrial materials have
self healing property, their safety, efficacy,
and reliability are significantly improved.
Rubber tree
5. : Damage and Repair cycleRef - 1
Reactive end groups can be free radicals
and/or –C=C–, –COOH, –NH2 , –OH, –Si–O,
SH/S–S, or –C=O
6. Thermodynamics of self-healing
The self- repairing process can be viewed as series of chain conformational
changes and this approach provided the molecular weight (M) dependence of
repair time : (Tr) ∝ M3 implying that lower molecular weight polymers exhibit
favorable repairing conditions.
Fracture stress (s) is related to M and (Tr) via : (s) ∝ (Tr/M) 1/4
Healing efficiency R(s) can be defined by the extent of the recovery with
respect to its initial post-damage state as the ratio of fracture stress after and
before healing R(s) = [s Healed / s Initial ]
7. Entropy Changes - Recoupling Model
+∆S from A to B occur due to the V↑ near
created interfaces which will ↑ the number
of arrangements available for a given state.
Driven by the +∆S as well as density gradients
near damaged areas, chain ends will
continuously expand into open voids and thus
fill the damage.
Therefore, flexibility (f) of chains becomes a
critical parameter in rebonding of chains
Ref – (1)
8. Gibbs Free Energy
The ∆G = 0 kJ/mol plane
represents polymer chains at
equilibrium. Above the ∆G = 0
plane (∆G < 0), spontaneous
repairs occur, whereas below the
∆G plane (∆G > 0), self-healing will
not take place.
The solid red curve shows how ∆G
is affected by the ↑N values (high
M) , ∆G = -RTln(N)
Ref- (1)
9. Self Healing Reactions
The reactive groups that formed during chain cleavage facilitate rebonding to
achieve successful self-healing. They include free radicals, –C=C–, –COOH, –
NH2, –OH, –SH/S-S, –Si– O, S–S, –C=O, and/or formation of cyclic structures.
A few classes of reactions that offer self-healing of polymers include covalent
bonding, supramolecular chemistry, H-bonding, ionic interactions, and pi–pi
stacking.
On a physical site, extrinsic chemo-mechanical repairs focused on
encapsulation, remote self-healing and shape memory assisted polymers.
10. Intrinsic systems
The material is inherently able to restore its integrity. Intrinsic systems often
require an external trigger for the healing to take place (such as thermo-
mechanical, electrical, photo-stimuli, etc.
5 main intrinsic self-healing strategies :
11. Based on covalent bond formation
DIELS-ALDER (DA) AND RETRO-DIELS-ALDER (rDA) REVERSIBLE REACTION
The DA reaction is a cycloaddition reaction between a conjugated diene
and a substituted alkene. The most relevant aspects of the (DA) reaction is
its thermal reversibility, known as the (rDA) reaction.
These reactions provide an efficient way to prepare remendable polymers,
which can go through repeated cycles of damage and repair at same site.
12. The polymeric material was stressed to complete failure and
subsequently healed by heating to 90–120 degree C, followed by cooling to
room temperature. The healed polymer recovered to 60% of the initial
strength. The chain ends were joined by a key-lock mechanism
DA and rDA Reversible Reaction
Ref –(3)
13. Non covalent Bonds - Supramolecular Networks
The networks can be remodeled rapidly and reversibly – from fluid- like, low
density, high free volume properties, to solid-like, lower free volume, elastic
and plastic networks.
There are, however, disadvantages. These polymers usually exhibit lower
T(g) , thus resulting in relatively soft materials utilized in specific
applications.
4 approaches to supramolecular bonds:
14. Hydrogen Bonding
The cross-linking occurs by intermolecular interactions of the monomer
units and/or the side chains by using H- bonds
The reversibility of non-covalent bonds allows repair to take place at the
molecular level to fully restore the original material properties. Moreover,
the crack and adhesions can be carried out repeatedly.
Fatty dimer acids were condensed with diethylene triamine and then
reacted with urea.
15. Hydrogen Bonding
H-bonded materials (amidoethyl imidazolidone, di(amido ethyl) urea and
diamido tetraethyl triurea) formed the self-healable elastomers. When a
rod-shaped rubber was cut in half using a razor, the cut rubber immediately
mends after being broken; the gel can be lifted against its own weight. The
repaired rubber adheres strongly to each other without a crack by extension
and shrinkage.
Ref –(3)
16. Self-healing ionomers
Ionomers are thermoplastic ionic polymers, consisting of hydrocarbon
chains bearing carboxylic acid groups that are neutralized with metal or
quaternary, ammonium ions.
The healing process occurred via thermal reversibility of the ionic
interaction.
Friction causes melt.
Elastically rebounds.
Polymer still molten,
able to reform at the
damage site.
Ref –(5)
17. Extrinsic Systems
In extrinsic systems, the healing agents are separated from the surrounding
polymer in microcapsules or vascular networks, which after material
damage/cracking release their reactive fluid into the crack plane, and allow
the restoration of material functionalities.
Extrinsic self-healing materials can achieve healing efficiencies over 100%
even when the damage is large.
There are two modes of the repair activity:
1. Self-healing in terms of healant loaded pipes (tubes)
2. Self-healing in terms of healant loaded microcapsules.(Spheres)
18. Hollow glass tubes and glass fibers
The core technique lies in filling the brittle-walled vessels with polymerizable
medium, which should be fluid at least at the healing temperature.
Subsequent polymerization of the chemicals flowing to the damage area
plays the role of crack elimination.
Three types of healing system were developed :
All hollow pipes
contained only one
kind of resin
Resin in one pipe and
epoxy hardener in
other
Pipes and spheres are
used simultaneously
19. Microcapsules
The principle of this approach resembles the aforesaid pipelines but the
containers for storing healing agent are replaced by fragile microcapsules.
20. Carbon Nano Tubes
(SWCNs) can be used as nano-reservoirs
for healing agents where the catalytic
trigger molecules are either wrapped
around the SWCNs or are dispersed in the
matrix.
Several factors to determine the amount
of healing agent that can be stored in the
SWCN -are the SWCN diameter,
orientation, dispersion, loading density
,type of the matrix and the healing agent
Ref –(5)
21. Electrically conductive and Resistance heating self-healing polymers
A series of N-heterocyclic carbenes (NHCs) were synthesised as good
electronic conductors.
The polymerised NHCs cut with a razor blade, and a smoothing was noticed
after heating the polymer to 200 degree C for 25 minutes.
Ref –(5)
22. Shape Memory Assisted Self Healing
Materials capable of recovering from a temporary shape (switching phase) to
a memorized permanent shape (stable network phase) when triggered by
external stimuli.
The transition fixes the cracks and damage to original shape.
These include Carbon- Nanoparticles, Metal oxide nanoparticles etc.
24. Applications of Self Healing Materials
Medical dental/ artificial body replacements
Nowadays an artificial bone replacement can last up
to 10 - 15 years. Good biocompatible self-healing
polymer composites may extend this time. In
dentistry, it can be used In making artificial teeth and
tooth filling materials.
Aero/Space
Having satellites made of lighter self-healing polymer
materials instead of metal, is a very cost-effective
solution & will increase longer flight durations. And
finally, safety of air and space crafts can be improved
by using self-healing components
25. Applications of Self Healing Materials
Military
Having armor, body protection that could
heal itself even during the battle will be
beneficial for the Army. Air force and Navy
can additionally benefit from fast self
disappearing holes in the skin of a jet or ship.
A prototype of such material already exists.
Dupont’s Surlyn® show good properties to
heal after ballistic damage.
Ref –(4)
26. Applications of Self Healing Materials
Paints/Coatings
One of the first commercial self-healing
materials, “Scratch Guard Coat” was released by
Nisan in December of 2005. With Scratch Guard
Coat a car’s scratched surface will return to its
original state anywhere from one day to a week,
depending on temperature and the depth of the
scratch. Moreover, the paint is hydrophobic.
28. Problems & Challenges
1. Storage of healing agent inside the material for a long period of time. This is
especially difficult inside of polymeric materials, which are intrinsically
permeable on molecular level.
2. The healing agent sometimes start reacting either with the surrounding
material or with matrix itself.
3. Finally, the healing agent should be strongly bound to the material, and be
stable with respect to the surrounding environment. This indeed is typically
the simplest problem, which is however, restrictive to the type of the
healing agent.
29. Conclusion
Activities in the field of self-healing polymers and polymer composites not
only focus on mechanical and chemical approaches to improving the
durability of materials but also involves new damage detection technique
incorporated.
From a long-term point of view, synthesis of brand new polymers
accompanied by intrinsic self-healing function through molecular design
would be a reasonable solution. Working out the solutions would certainly
push polymer sciences and engineering forward.
2 USA based companies have started commercializing the products
30. References
1. ‘Self-healing polymeric materials’ - Ying Yang and Marek W. Urban , DOI: 10.1039/c3cs60109a
, The Royal Society of Chemistry ,2013 .
2. ‘Chemical and physical aspects of self-healing materials’ - Ying Yang, Xiaochu Ding, Marek W.
Urban, DOI: 10.1016/j.progpolymsci.2015.06.001 ,Progress in polymer science, June 2015 .
3. ‘Self-Healing Polymers’ - Yoshinori Takashima and Akira Harada , DOI 10.1007/978-3-642-
36199-9_50-1 , Encyclopedia of Polymeric Nanomaterials,2013.
4. ‘Synthesis of Self-Healing Polymers by Scandium-Catalyzed Copolymerization of Ethylene and
Anisylpropylenes’ - Haobing Wang, Yang Yang, Masayoshi Nishiura, Yuji Higaki, Atsushi
Takahara and Zhaomin Hou, DOI: 10.1021/jacs.8b13316 ,Journal of American Chemical
Society,2019.
5. ‘Self-healing and self-mendable polymers’ - Jay A. Syrett, C. Remzi Becer and David M.
Haddleton , DOI: 10.1039/c0py00104j , The Royal Society of Chemistry ,2010 .
6. Wikipedia - https://en.wikipedia.org/wiki/Self-healing_material