This document provides an overview of topics that will be covered in a Polymer Chemistry course. The topics include: introduction to polymer chemistry including history, definitions, classifications and structures; mechanisms and nomenclature of polymers; chemistry of polymerization including chain, step and ring opening polymerization; polymerization techniques; polymer additives; molecular weights of polymers; silicone and cellulose polymers; and polymer reactions. The course will reference several textbooks on polymer science and chemistry.
Polymer - a long chain molecule made up of many small identical units of Monomer is known as Polymer.
Monomer - the smallest repeating unit is known as Monomer.
Polymer is a molecule is obtained by natural and synthetic origin having group of Smallest repeating unit is known as polymer.
Polymer is important for increasing the stability of drug molecule, it is important to influencing the solubility of drug molecule, it is important to maintain the Physicochemical properties, it is important to maintain the prolong stability of drug molecule in extended period of time, it is important for influencing the Bioavailability of drug.
Polymer is important for Pharmaceutical industries and research purpose.
Polymerization Process and its Advantages , Disadvantage
1.Bulk Polymerization Process
2.Solution Polymerization Process
3.Suspension Polymerization Process
4.Emulsion Polymerization Process
Polymer:
A large molecule having high molecular mass formed by joining a repeating unit of smaller molecules (monomers) through a covalent bonding is called as polymer. Monomer is small individual repeating unit or molecules are called monomers. Monomer is basic unit of polymer. E.g. In polyethylene is an ethylene is monomer. Polymers usually contain more than five monomers, and some may contain hundreds or thousands of monomers in each chain. The process by which polymers are formed by linking monomers through chemical reaction called polymerization.
1. Physical Properties: The molecular weight of a polymer molecule is the product of the degree of polymerization and the molecular weight of the repeating unit. The polymer molecules are not identical but are a mixture of many species with different degrees of polymerization, that is, with different molecular weights. Therefore, in the case of polymers we talk about the average values of molecular weights.Polymerization reactions produce a distribution of molecular weights and shapes. Polymer molecular weight could be expressed as number average molecular weight, weight average molecular weight, and polydispersity.
The polymer chains being very large hence found in the two polymeric forms. Crystalline Polymers:
Lamellar crystalline form in which the chains fold and make lamellar structure arranged in the regular manner. Amorphous Polymers: Amorphous form in which the chains are in the irregular manner.A typical range of crystallinity can be defined as amorphous to highly crystalline. The polymers having simple structural chains as linear chains and slow cooling rate will result in good crystallinity as expected.
02. Thermal Properties:
a)Polymer Glass Transition temperature:
In the study of polymers and their applications, it is important to understand the concept of the glass transition temperature, Tg. As the temperature of a polymer drops below Tg, it behaves in an increasingly brittle manner. As the temperature rises above the Tg, the polymer becomes more rubberlike. Thus, knowledge of Tg is essential in the selection of materials for various applications. In general, values of Tg well below room temperature define the domain of elastomers and values above room temperature define rigid, structural polymers.
The objective of polymer synthesis is to efficiently assemble macromolecules with precisely controlled structures, so as to maximize their utility for a given application. Polymerization can occur via a variety of reaction mechanisms that vary in complexity due to the functional groups present in the reactants and their inherent steric effects.There are two major types of' polymerization methods used to convert small molecules (monomers) into polymers. These methods were originally referred to as addition or chain growthpolymerization and condensation or step growth polymerization. The coordination polymerizationis another variant of chain-growth polymerization.
Polymer - a long chain molecule made up of many small identical units of Monomer is known as Polymer.
Monomer - the smallest repeating unit is known as Monomer.
Polymer is a molecule is obtained by natural and synthetic origin having group of Smallest repeating unit is known as polymer.
Polymer is important for increasing the stability of drug molecule, it is important to influencing the solubility of drug molecule, it is important to maintain the Physicochemical properties, it is important to maintain the prolong stability of drug molecule in extended period of time, it is important for influencing the Bioavailability of drug.
Polymer is important for Pharmaceutical industries and research purpose.
Polymerization Process and its Advantages , Disadvantage
1.Bulk Polymerization Process
2.Solution Polymerization Process
3.Suspension Polymerization Process
4.Emulsion Polymerization Process
Polymer:
A large molecule having high molecular mass formed by joining a repeating unit of smaller molecules (monomers) through a covalent bonding is called as polymer. Monomer is small individual repeating unit or molecules are called monomers. Monomer is basic unit of polymer. E.g. In polyethylene is an ethylene is monomer. Polymers usually contain more than five monomers, and some may contain hundreds or thousands of monomers in each chain. The process by which polymers are formed by linking monomers through chemical reaction called polymerization.
1. Physical Properties: The molecular weight of a polymer molecule is the product of the degree of polymerization and the molecular weight of the repeating unit. The polymer molecules are not identical but are a mixture of many species with different degrees of polymerization, that is, with different molecular weights. Therefore, in the case of polymers we talk about the average values of molecular weights.Polymerization reactions produce a distribution of molecular weights and shapes. Polymer molecular weight could be expressed as number average molecular weight, weight average molecular weight, and polydispersity.
The polymer chains being very large hence found in the two polymeric forms. Crystalline Polymers:
Lamellar crystalline form in which the chains fold and make lamellar structure arranged in the regular manner. Amorphous Polymers: Amorphous form in which the chains are in the irregular manner.A typical range of crystallinity can be defined as amorphous to highly crystalline. The polymers having simple structural chains as linear chains and slow cooling rate will result in good crystallinity as expected.
02. Thermal Properties:
a)Polymer Glass Transition temperature:
In the study of polymers and their applications, it is important to understand the concept of the glass transition temperature, Tg. As the temperature of a polymer drops below Tg, it behaves in an increasingly brittle manner. As the temperature rises above the Tg, the polymer becomes more rubberlike. Thus, knowledge of Tg is essential in the selection of materials for various applications. In general, values of Tg well below room temperature define the domain of elastomers and values above room temperature define rigid, structural polymers.
The objective of polymer synthesis is to efficiently assemble macromolecules with precisely controlled structures, so as to maximize their utility for a given application. Polymerization can occur via a variety of reaction mechanisms that vary in complexity due to the functional groups present in the reactants and their inherent steric effects.There are two major types of' polymerization methods used to convert small molecules (monomers) into polymers. These methods were originally referred to as addition or chain growthpolymerization and condensation or step growth polymerization. The coordination polymerizationis another variant of chain-growth polymerization.
* Introduction to polymers.
* Polymerization.
* Characteristics of an ideal polymer.
* Classification of polymer on different bases- Origin, Monomer,
Thermalresponse, Mode of formation,structure & Biodegradability
* Some other parameters of polymer classification - Crystallinity & BackboneAtom
* Conclusion
Intrduction to polymers in materials science and engineeringmojeedadisa
Introduction to Polymers in Materials Science and Engineering
Unveiling the Building Blocks of Our World
This presentation delves into the fascinating world of polymers, the ubiquitous materials that shape our everyday lives. We'll explore their fundamental characteristics, how they're formed, and the diverse applications they enable in materials science and engineering.
Key areas covered:
What are polymers? (definition, structure, types)
Unveiling the building blocks: monomers and polymerization
Natural vs. synthetic polymers: Exploring their origins
Tailoring properties for specific applications
Processing techniques: Bringing polymers to life
From concept to creation: Applications across industries
Join us as we discover the power of polymers and their remarkable impact on shaping our world!
Polymers are very large molecules made when hundreds of monomers join together to form long chains .
The word POLYMER comes from the Greek words poly means many and mer means parts .
Polymer is used as a synonym for plastic .
All plastics are polymers , but not all polymers are plastics
Polymers play a very important role in human life. Our body is made of lot of polymers, e.g. Proteins, enzymes, etc. Other naturally occurring polymers like wood, rubber, leather and silk are have wide application. Now a day synthetic polymer like useful plastics, rubbers and fiber materials are synthesized. presentation includes introduction classification and preparation methods. Polymers play a very important role in human life. Our body is made of lot of polymers, e.g. Proteins, enzymes, etc. Other naturally occurring polymers like wood, rubber, leather and silk are have wide application. Now a day synthetic polymer like useful plastics, rubbers and fiber materials are synthesized. Leo Baekeland patented the first totally synthetic polymer called Bakelite (1910). Bakelite is a versatile, durable material prepared from low-cost materials phenol and formaldehyde and was the most important synthetic polymer material. In the 1920s Hermann Staudinger showed that polymers were high-molecular-weight compounds held together by normal covalent bonds.
The suffix in polymer ‘mer’ is originated from Greek word meros – which means part. The word polymer is thus coined to mean material consisting of many parts or mers. A macromolecule having high molecular mass (103-107u) and generally not a well-defined structure or molecular weight. The macromolecules formed by joining of repeating structural units on a large scale. The repeating structural units are simple and reactive molecules linked to each other by covalent bonds. This process of formation of polymers from respective monomers is called polymerization. Most of the polymers are basically organic compounds, however they can be inorganic (e.g. silicones based on Si-O network).
Introduction
Types of polymer
Classification of Polymer
Polymerization
Biodegradable Polymer
Application of biodegradable polymer
Natural polymer
They occur naturally and are found in plants and animals. For example, proteins, starch, cellulose, and rubber. To add up, we also have biodegradable polymers called biopolymers.
Semi-synthetic Polymers:
They are derived from naturally occurring polymers and undergo further chemical modification. For example, cellulose nitrate, and cellulose acetate.
Synthetic Polymers
These are man-made polymers. Plastic is the most common and widely used synthetic polymer. It is used in industries and various dairy products. For example, nylon-6, 6, polyether’s etc.
Thermosetting polymersThese polymers greatly improve the material’s mechanical properties. It provides enhanced chemical and heat resistance. For example, phenolics, epoxies, and silicones.Addition Polymerization: For Example, poly ethane, Teflon, Polyvinyl chloride (PVC)Condensation Polymerization: Example, Nylon -6, 6, perylene, polyesters.
Types of fibres,their classification,applications,properties, and structures
Further more polymers,their types and different type chemical bonds present in fibres,
From the stone age to the age of computers, a significant development is self evident in the materials that make our daily life comfortable. One of these revolutionary materials in the modern world is polymers. Polymers are natural or synthetic substances composed of very large molecules, called macromolecules, which are multiples of simpler chemical units called monomers. These are present in almost every aspect of modern day lives because of their vast spectrum of properties. Natural polymers like wool, cotton, and silk are present in our society long before the notion itself. In 1869 John Wesley Hyatt invented celluloid, the first synthetic plastic, while searching for an artificial replacement for ivory. It was not until 1907 when polymers entered the industrial sector with the invention of Bakelite, the first fully synthetic plastic, containing zero naturally occurring molecules. These inventions later emerged as a field of macromolecular chemistry, a field closely associated with the name of Herman Staudinger, who received the Nobel Prize in 1953 for first proposing the idea of polymerization a process of reacting monomer molecules together in a chemical reaction to form polymer chains . Since then, there have been several developments in the synthesis of various polymers, contributing to six more Nobel prizes associated with the field of polymeric sciences. In this review we will discuss some of the most commonly used polymers in everyday life. Dr. Pushpraj Singh "Polymers Used in Everyday Life" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-6 | Issue-1 , December 2021, URL: https://www.ijtsrd.com/papers/ijtsrd48033.pdf Paper URL: https://www.ijtsrd.com/chemistry/polymer-chemistry/48033/polymers-used-in-everyday-life/dr-pushpraj-singh
Earliest Galaxies in the JADES Origins Field: Luminosity Function and Cosmic ...Sérgio Sacani
We characterize the earliest galaxy population in the JADES Origins Field (JOF), the deepest
imaging field observed with JWST. We make use of the ancillary Hubble optical images (5 filters
spanning 0.4−0.9µm) and novel JWST images with 14 filters spanning 0.8−5µm, including 7 mediumband filters, and reaching total exposure times of up to 46 hours per filter. We combine all our data
at > 2.3µm to construct an ultradeep image, reaching as deep as ≈ 31.4 AB mag in the stack and
30.3-31.0 AB mag (5σ, r = 0.1” circular aperture) in individual filters. We measure photometric
redshifts and use robust selection criteria to identify a sample of eight galaxy candidates at redshifts
z = 11.5 − 15. These objects show compact half-light radii of R1/2 ∼ 50 − 200pc, stellar masses of
M⋆ ∼ 107−108M⊙, and star-formation rates of SFR ∼ 0.1−1 M⊙ yr−1
. Our search finds no candidates
at 15 < z < 20, placing upper limits at these redshifts. We develop a forward modeling approach to
infer the properties of the evolving luminosity function without binning in redshift or luminosity that
marginalizes over the photometric redshift uncertainty of our candidate galaxies and incorporates the
impact of non-detections. We find a z = 12 luminosity function in good agreement with prior results,
and that the luminosity function normalization and UV luminosity density decline by a factor of ∼ 2.5
from z = 12 to z = 14. We discuss the possible implications of our results in the context of theoretical
models for evolution of the dark matter halo mass function.
What is greenhouse gasses and how many gasses are there to affect the Earth.moosaasad1975
What are greenhouse gasses how they affect the earth and its environment what is the future of the environment and earth how the weather and the climate effects.
This pdf is about the Schizophrenia.
For more details visit on YouTube; @SELF-EXPLANATORY;
https://www.youtube.com/channel/UCAiarMZDNhe1A3Rnpr_WkzA/videos
Thanks...!
Nutraceutical market, scope and growth: Herbal drug technologyLokesh Patil
As consumer awareness of health and wellness rises, the nutraceutical market—which includes goods like functional meals, drinks, and dietary supplements that provide health advantages beyond basic nutrition—is growing significantly. As healthcare expenses rise, the population ages, and people want natural and preventative health solutions more and more, this industry is increasing quickly. Further driving market expansion are product formulation innovations and the use of cutting-edge technology for customized nutrition. With its worldwide reach, the nutraceutical industry is expected to keep growing and provide significant chances for research and investment in a number of categories, including vitamins, minerals, probiotics, and herbal supplements.
THE IMPORTANCE OF MARTIAN ATMOSPHERE SAMPLE RETURN.Sérgio Sacani
The return of a sample of near-surface atmosphere from Mars would facilitate answers to several first-order science questions surrounding the formation and evolution of the planet. One of the important aspects of terrestrial planet formation in general is the role that primary atmospheres played in influencing the chemistry and structure of the planets and their antecedents. Studies of the martian atmosphere can be used to investigate the role of a primary atmosphere in its history. Atmosphere samples would also inform our understanding of the near-surface chemistry of the planet, and ultimately the prospects for life. High-precision isotopic analyses of constituent gases are needed to address these questions, requiring that the analyses are made on returned samples rather than in situ.
Introduction:
RNA interference (RNAi) or Post-Transcriptional Gene Silencing (PTGS) is an important biological process for modulating eukaryotic gene expression.
It is highly conserved process of posttranscriptional gene silencing by which double stranded RNA (dsRNA) causes sequence-specific degradation of mRNA sequences.
dsRNA-induced gene silencing (RNAi) is reported in a wide range of eukaryotes ranging from worms, insects, mammals and plants.
This process mediates resistance to both endogenous parasitic and exogenous pathogenic nucleic acids, and regulates the expression of protein-coding genes.
What are small ncRNAs?
micro RNA (miRNA)
short interfering RNA (siRNA)
Properties of small non-coding RNA:
Involved in silencing mRNA transcripts.
Called “small” because they are usually only about 21-24 nucleotides long.
Synthesized by first cutting up longer precursor sequences (like the 61nt one that Lee discovered).
Silence an mRNA by base pairing with some sequence on the mRNA.
Discovery of siRNA?
The first small RNA:
In 1993 Rosalind Lee (Victor Ambros lab) was studying a non- coding gene in C. elegans, lin-4, that was involved in silencing of another gene, lin-14, at the appropriate time in the
development of the worm C. elegans.
Two small transcripts of lin-4 (22nt and 61nt) were found to be complementary to a sequence in the 3' UTR of lin-14.
Because lin-4 encoded no protein, she deduced that it must be these transcripts that are causing the silencing by RNA-RNA interactions.
Types of RNAi ( non coding RNA)
MiRNA
Length (23-25 nt)
Trans acting
Binds with target MRNA in mismatch
Translation inhibition
Si RNA
Length 21 nt.
Cis acting
Bind with target Mrna in perfect complementary sequence
Piwi-RNA
Length ; 25 to 36 nt.
Expressed in Germ Cells
Regulates trnasposomes activity
MECHANISM OF RNAI:
First the double-stranded RNA teams up with a protein complex named Dicer, which cuts the long RNA into short pieces.
Then another protein complex called RISC (RNA-induced silencing complex) discards one of the two RNA strands.
The RISC-docked, single-stranded RNA then pairs with the homologous mRNA and destroys it.
THE RISC COMPLEX:
RISC is large(>500kD) RNA multi- protein Binding complex which triggers MRNA degradation in response to MRNA
Unwinding of double stranded Si RNA by ATP independent Helicase
Active component of RISC is Ago proteins( ENDONUCLEASE) which cleave target MRNA.
DICER: endonuclease (RNase Family III)
Argonaute: Central Component of the RNA-Induced Silencing Complex (RISC)
One strand of the dsRNA produced by Dicer is retained in the RISC complex in association with Argonaute
ARGONAUTE PROTEIN :
1.PAZ(PIWI/Argonaute/ Zwille)- Recognition of target MRNA
2.PIWI (p-element induced wimpy Testis)- breaks Phosphodiester bond of mRNA.)RNAse H activity.
MiRNA:
The Double-stranded RNAs are naturally produced in eukaryotic cells during development, and they have a key role in regulating gene expression .
The ASGCT Annual Meeting was packed with exciting progress in the field advan...
Introduction to polymer chemistry
1. T.Y.B.Sc.
Paper VI [CH-336 B]
Prof. Amit Divhare
Department of Chemistry
Vidya Pratishthan’s Arts, Science & Commerce College, Baramati.
Email- amitdivhare@rediffmail.com
2. Polymer Chemistry (CH-336B)
Topic –
1. Introduction to Polymer Chemistry
History in Polymers, Polymer. definition, Preparation, Classification, Structures, Chemical bonding
2. Mechanism and Nomenclature of Polymers
a) Polymerization Mechanism, b) Nomenclature of Polymers-i) Common/ Trivial names ii)Source-Based names, iii)
Structure-Based names (Non IUPAC), iv) IUPAC Structure-based and Linkage based nomenclature system and v)
Trade names/ Brand names & Abbreviations.
3. Chemistry of Polymerization
a) Introduction, b) Chain Polymerization: Free radical Polymerization, Ionic polymerization, Coordination
polymerization- Ziegler-Natta catalyst c) Step Polymerization: Polycondensation, Polyaddition polymerization, and
Ring Opening polymerization.
4. Polymerization Techniques
Bulk polymerisation, Solution polymerization, Suspension polymerization, Emulsion polymerization, Melt
polycondensation, Solution Polycondensation, Interfacial condensation, electrochemical polymerisation, Salient
features of different polymerization techniques
3. 5. Polymer Additives
Fillers & Reinforcement, Plasticizers, Antioxidants & Thermal Stabilizers (Heat, Ultraviolet stabilizers, Fire retardants, Colourants,
Antistatic agents & Curing agents.
6. Molecular Weights of Polymers
Average Molecular weight, Number Average & Weight Average Molecular weight, Molecular weight & degree of polymerisation,
Practical significance of polymer molecular weights, b)Molecular weight determination by End Group Analysis & Viscosity method
and c) Problems based on Number Average & Weight Average Molecular weight.
7. Silicone and Cellulose Polymers
a) Introduction, Synthesis, Reactions, Uses of Silicone polymers, b) Cellulose & Derivatives of cellulose: Rayon, Cellophane,
Cellulose nitrate, Cellulose acetate and their uses.
8. Polymer Reactions
Introduction, Hydrolysis, Hydrogenation. Addition and Substitution reactions, Cross-linking reactions, Cure reactions, Reactions of
various aliphatic and aromatic pendent groups in polymers.
Reference Books:
1. Polymer Science by V.R. Gowarikar, N.V.Vishvanathan, JaydevShreedhar NewAge International Ltd. Publisher 1996. (Reprint 2012)
2. Textbook of Polymer Science by Fred Billmeyer, 3 Edn. A Wiely-IntersciencePublication John Wiely & Sons New York 1984.
3. Introductory Polymer Chemistry by G.S. Misra New Age International (P) Ltd. Publisher 1996.
4. Principle of Polymer Science by P. Bahadur, N.V. Sastry. 2 Edn, Narosa Publishing House.
5. Polymer Chemistry by Ayodhya Singh, 2008, Published by Campus Book International, NewDelhi.
6. Organic Polymer Chemistry by Jagdamba Singh, R.C. Dubey, 4 Edn, 2012.
4. Introduction to Polymer Chemistry
1. History
2. Important term
Polymer
Monomer
Polymerization
Degree of polymerization
Functionality of monomer
Virgin Polymer
Compounding
5. 3. Classification
Natural and synthetic polymers
Organic and inorganic polymers
Homo polymers and co-polymers
Homochain and Hetrochain polymers
Thermoplastics and thermosetting plastics
Addition and condensation polymers
Linear, branched and cross linked polymers
Alternative, random, block and graft copolymers
Plastic, elastomers, rubber and liquid resin
Isotactic, syndotactic and atactic polymers
4. Important application of some polymers
6. What are polymers ?
1. The term ‘polymer’ is derived from the Greek words, poly-many and meros-unit.
2. A polymer is defined as a macromolecule with very high molecular weight and is made by joining of
large number of small molecules of monomer.
3. Polymer molecules have certain structural unit repeating large number of times.
8. History
1492 - Columbus discovered south America and he found playing and enjoying game with solid ball collected from
rubber tree (crying tree). Grow rubber industry.
Rubber was named by the chemist Joseph Priestley who found that a piece of solidified latex gum was good for
rubbing out pencil marks on paper. In Great Britain, erasers are still called “rubbers”. “Crying trees”
1839- Charles Goodyear
Discovered, through a lucky accident, that by heating the latex with sulfur, the properties were changed making the
rubber more flexible and temperature stable. That process became known as vulcanization.
1846-John Wesley Hyatt
Celluloid – Cellulose nitrate and camphor (as plasticizer).
1st artificial thermoplastic material used in photographic film.
9. 1905- Leo Baekeland
Bakelite- phenol formaldehyde resin (not soften by heat).
1st truly synthetic plastic.
Bakelite was first used to make billiard balls, but, later, was used to make molded
insulation, valve parts, knobs, buttons, knife handles, many types of molded plastic
containers for radios and electronic instruments, and more.
1911 – Rayon
1st synthetic fibre developed as a replacement of silk.
Dress made from silk
1912 –Jacques Brandenburger
Cellophane- famous transparent materials.
Phenol-Formaldehyde resin
10. 1920 – Staudinger “Macromolecule Hypothesis”
Demonstrations of both natural and synthetic polymers.
Polymer is Giant molecule.
-Not aggregate like colloid or cyclic compound
-long chain like molecule
-formulated a polymeric structure for rubber based on a repeating isoprene unit.
A polymer is a macromolecule…….but a macromolecule may not be a polymer. Nobel Prize-1953
1927-PVC
1931-PMMA and Neoprene
1938- Nylon
1941- LDPE
1943- Silicone rubber
1947- Epoxy resin
1957-HDPE
11. Important term
Monomers-
1. The monomer molecules act as building block of polymer.
2. Monomer is defined as the low molecular weight compound which can be converted into a polymer.
3. A monomer molecule has at least two easily reacting positions in the form of either functional groups or in the form of
C=C.
4. The functional group in the monomer organic molecules can be like –OH, COOH, -NH2, CN, COOR, Cl, cyclic amide
(lactam group), cyclic acid anhydride group.
5. A C=C contain a weak π-bond and it can easily broken by action of heat or a reagent. When π-bond is broken, two
positions become available for the polymerization.
12. Polymerization
1. The chemical process in which a large number of monomer molecules get joined to form the
polymer molecules is known as polymerization.
3.The number of monomer molecules that get joined to form polymer molecule is generally greater
than 100 and may be upto many thousand.
13. Degree of polymerization
1. The number of repeating units (monomers) in polymer chain is called degree of polymerization
2. In general strength of polymer increases with increase in degree of polymerization. The DP should such
that the polymer has at least 20,000 molecular weight, for the polymer to have desirable strength properties. In
the case of vinylic polymers DP range of 200 to 400.
3.Degree of polymerization can be controlled by controlling condition of polymerization such as temperature,
time, concentration of monomer, catalyst etc.
14. 4. Relation of degree of polymerization and molecular weight of polymer
Molecular weight of polymer = DP X molecular weight of monomer
M = DP X Mo
For e.g. Molecular weight of polyethylene with DP =1000 will be 28000.
Molecular weight of polyethylene =1000 X 28
= 28000.
Virgin Polymer - Pure form of the polymer is called virgin polymer.
Compounding - The process involving incorporation of ingredients such as plasticizers,
vulcanizing agent, stabilizers, fillers, curative, colouring agent, flame retardant,
lubricants with polymer is known as compounding.
15. Functionality of Monomers-
1. Functionality of Monomers is defined as the number of reactive positions or groups in the molecule of
monomer.
2. Bifunctional of Monomers-Monomer molecule contain two easily reacting positions.
It forms a linear polymer.
16. 3.Trifunctional of Monomers-Monomer molecule contain three easily reacting positions.
It forms a branched polymer or limited cross-linked polymer.
4.Tetrafunctional of Monomers-Monomer molecule contain four easily reacting positions.
It forms a three dimensional network or cross-linked polymer.
17. Natural polymers Synthetic polymers
1. Polymer which are isolated from natural
material are called natural polymer.
2. They are biodegradable.
3. For e.g. cotton, silk, wool, rubber etc.
1. Polymer which are synthesized from low
molecular weight compound are called
synthetic polymer.
2. They are non-biodegradable.
3.For e.g. Polyethylene, polystyrene etc.
Classification of polymers
On the basis of source- Natural and synthetic polymers
18. Organic polymers Inorganic polymers
1. A Polymer whose backbone chai essentially made of
carbon atom is called as organic polymer.
2. Most of organic polymers are linear.
3. They are generally soft.
4. They are stable upto 300oC.
5. They are less resistance to acid and alkalies.
6. For e.g. cellulose, nylon, Polyethylene, polystyrene etc.
1. A Polymer whose backbone chain not made of carbon atom
is called as inorganic polymer.
2. Most of inorganic polymers are cross-linked.
3. They are generally hard and brittle.
4. They are stable at higher temp. than 300oC.
5. They are more resistance to acid and alkalies.
6. For e.g.
Polysilicones,polyphosphazenes,polyaminoboranes etc.
On the basis of backbone chain-Organic and inorganic polymers
19. Homopolymer Co-polymer
1. A Polymer is formed from only one type of
monomer is called as homopolymer.
2. It is hard and brittle.
3. It has high Tg Value.
4. They generally requires external plasticizer.
5. For e.g. Polyethylene, Polystyrene etc.
1. A Polymer is formed from two different
type of monomer is called as co-polymer.
2. It is soft and flexible.
3. It has low Tg Value.
4. They are internally plasticized.
5. For e.g. Nylon 6, styrene-butadiene rubber.
On the basis of composition-Homopolymer and co-polymer
20. Thermoplastics Thermosetting plastics
1. The polymers which can be soften on heating and harden
on
cooling room temperature are called Thermoplastics.
2. They are often formed by addition polymerization.
3. They are linear polymers.
4. They can be reshaped and reused.
5. They are soft, weak and less brittle.
6. They are usually soluble in organic solvent.
7. For e.g. nylon, polyethylene, PVC etc
1. The polymers are hard and infusible on heating are
called
thermosetting plastics.
2. They are often formed by condensation polymerization.
3. They are cross linked polymers.
4. They cannot be reshaped and reused.
5. They are hard, strong and more brittle.
6. They are insoluble in organic solvent.
7. For e.g. Phenol-formaldehyde resin,
Malemine- formaldehyde resin etc
On the basis of thermal behavior-Thermoplastics and thermosetting plastics.
21. Homochain polymer Hetrochain polymer
1. A Polymer is formed from only one kind
of atom is called as homopolymer.
2. –C-C-C-C-C-C-
3. Generally obtained by addition polymerization
4. For e.g. Polyethylene, polystyrene etc.
1. A Polymer is formed from more than one
type of atom is called as hetrochain polymer.
2. –C-C-O-C-C-O-
3. Generally obtained by condensation polymerization
4. For e.g. Nylon 6, Polyamide, polyester etc.
On the basis of chain atom- Homochain and hetrochain polymers
22. Addition polymers Condensation polymers
1. The polymers formed by addition reaction are called
Addition polymers.
2. Molecular mass is a whole number multiple of the monomer.
3. They involve one monomer unit.
4. Monomers are unsaturated molecules.
5. They are chain growth polymers.
6. For e.g. polyethylene, PVC etc
1. The polymers formed by condensation reaction are called
condensation polymers.
2. Molecular mass is not whole number multiple of the monomer.
3. They involve two or more monomer unit.
4. Monomers must have two reactive functional group.
5. They are step growth polymers.
6 .For e.g. Polyesters, Nylon6,6 etc.
On the basis on mode of polymerization- Addition and condensation polymers
23. On the basis of structure of polymers-Linear, branched chain and cross linked polymers
i) Linear polymers
These are polymers in which monomers are join together to form linear chain are called linear polymers.
Their molecules are closely packed and have high densities, high tensile strength and high melting point than branched and cross-linked polymers.
For e.g. HDPE, nylon, polyester, PVC etc.
ii) Branched chain polymers
These are polymers in which monomers are join together to form long chains with side chains or branches are called branched polymers
Their molecules are irregular packed and have low densities, low tensile strength and low melting point than linear polymers.
For e.g. LDPE, polypropylene, glycogen, starch etc.
iii) Cross-linked polymer
These are polymers in which monomers units are cross-linked together to form a three dimensional network are called linear polymers.
These polymers are hard, rigid and brittle because of network structure.
Polymers do not dissolve in solvents because all the polymer chains are covalently tied together, but they can absorb solvents.
For e.g. Bakelite, melamine formaldehyde resin etc.
24. On the basis of ultimate form and use-Plastics, Elastomers, rubbers, liquid resins
i) Plastics-
When polymers are shaped into hard and tough utility articles by the applied of heat and pressure, they are called as plastics.
The intermolecular forces between polymeric chains are intermediate between elastomers and fibers.
They are partially crystalline.
For e.g. PVC, PMMA, polystyrene etc.
ii) Elastomers-
The polymers that have elastic character like rubber (a material that can return to its original shape after stretching) are called elastomers.
These are the polymers which have weak intermolecular forces between the chains.
They are usually amorphous polymers.
For e.g natural rubber, butadiene rubber, neoprene etc.
25. iii) Fibres-
The long filament like polymer material whose length is at least 100 times its diameter is called as fibre.
These are the polymers which have strong intermolecular forces between the chains.
They are highly crystalline polymers.
For e.g. polyamides (nylon 6), polyesters (terylene) etc.
iv) Liquid Resins-
Polymers used as adhesives, potting compound sealants etc. in a liquid form are called as liquid resin.
For e.g. epoxy adhesives and Polysulphide sealants.
Epoxy resins
26. On the basis of configurations (tacticity) of polymers -Isotactic, syndotactic and atactic polymers
The arrangement of the substituents on the backbone of the polymer is called the tacticity of that polymer.
i) Isotactic polymer
Those polymers in which the arrangement of all substituent’s are on the same side of polymer chain are known as isotactic polymers.
Isotactic polymers are highly crystalline than syndiotactic and atactic polymers.
They are hard, high melting and less soluble.
Ziegler-Natta catalyst used for preparation of isotactic polymer.
ii) Syndiotactic polymers-
Those polymers in which the arrangement of all substituent’s are on the alternating side of polymer chain are known as syndiotactic polymers.
Syndiotactic polymers are less crystalline than isotactic polymers but they are more crystalline than atactic polymers.
They are hard, high melting and less soluble.
Ziegler-Natta catalyst used for preparation of syndiotactic polymer.
27. iii) Atactic polymers-
Those polymers in which the arrangement of all substituents is at random around main chain are known as atactic polymers.
Atactic polymers are less crystalline than isotactic and syndiotactic polymers.
They are softs, low melting and easily soluble.
Specific catalyst is not used for preparation of atactic polymers.
28. Copolymers -Alternative, random, block and graft copolymers
i) Alternative copolymer-
A co-polymer, in which the two monomer units are placed in alternative manners, is known as alternative co-polymers.
For e.g. styrene maleic anhydride copolymer.
ii) Random copolymer-
A co-polymer, in which the two monomer units are placed in random manners, is known as random co-polymers.
For e.g. Styrene butadiene rubber (SBR)
29. iii) Block copolymer-
The linear copolymer in which each monomer units form a block is known as block co-polymers.
For e.g. Polystyrene-block -Polybutadiene -block-Polystyrene (SBS rubber)
iv) Graft copolymer-
The branched copolymer in which each one monomer unit’s forms backbone of the polymer and another monomer
unit forms the branches is known as Graft co-polymers.
For e.g. Acrylonitrile – butadiene –styrene copolymer ABS rubber.