POLYMERS

1. Presented By ,
Miss. Janhavi Shirish Zope
M Pharmacy 1st year
Department : Pharmaceutics
R . G . SAPKAL COLLEGE OF PHARMACY
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2. CONTENTS
 Introduction
 Types of Polymer
 Classification of Polymer
 Characteristics of Polymer
 Application
 References
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3. INTRODUCTION
 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
N(CH2-CH2) (-CH2-CH2-)s
Ethylene Polyethylene
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4. TYPES OF POLYMER
 Natural Polymers
 Homopolymer
 Copolymer
 Thermoplastics
 Thermosets
 Long chain Polymers
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5. NATURAL POLYMERS
 Definition : Natural polymer is a polymer that results from
only raw materials that are found in nature .
 Some of these natural polymers include DNA and RNA
 Cotton , DNA , Wool , Wood are some of the naturally
occurring polymers .
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6. HOMOPOLYMER
 Homopolymers are synthesized from a single type of
monomer .
 Homopolymers are consists of chains with identical
bonding linkages to each monomer unit .
 This usually implies that the polymer is made from all
identical monomer molecules .
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7. COPOLYMER
 When two or more different monomers together to
polymerize their result is called as copolymer .
 This process is called as copolymerization .
 Types of Copolymer :
1) Statistical copolymer
2) Alternating copolymer
3) Block copolymer
4) Graft copolymer
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8. THERMOPLASTIC
 A type of plastic that can be softened by heat , hardened
by cooling , and then softened by heat over and over again
 Thermoplastic are not cross – linked polymer .
 Examples : Polyethylene , Nylon , Polyvinyl chloride .
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9. THERMOSETS
 Thermoset having the property of becoming permanently
hard and rigid when heated .
 Thermosets are hard and rigid at room temperature and do
not soften on heating .
 Examples : Epoxy resins , Phenolic resins , Unsaturated
polyester resins .
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10. LONG CHAIN POLYMERS
 A very long strand of repeating molecules linked together
by primary bond .
 Polymer chains are orient themselves in lines as they
enter a mold but may be annealed so they can recoil .
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11. CLASSIFICATION OF POLYMER
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12. BASED ON ORIGIN OF SOURCE
 Natural Polymer :- Polymers which are isolated from
natural materials are called as Natural Polymers . E.g. :
Cotton , silk , wool , rubber .
 Synthetic Polymer :- Polymers which are synthesized
from low molecular weight compounds are called as
Synthetic Polymers . E.g. : Polyethylene , nylon , terylene.
 Semisynthetic Polymers :- These polymers are mostly
derived from naturally occurring polymers by chemical
modification . E.g. : Rayon
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13. BASED ON STRUCTURE
 Linear Polymer : Molecules
form long chains without
branches.
 Branched Polymer : Molecules
having branch points that
connect 3 or more segments .
 Cross-Linked Polymer : It
includes interconnections
between chains .
 Network Polymer : A cross
linked polymer that includes
numerous interconnections
between chains .
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14. BASED ON MODE OF POLYMERISATION
 Additional Polymerization :
Same kind of monomers are straight forwardly added .
It is rapid chain reaction having chemically activated mers
.
Each reaction sets up the condition for another to proceed
.
It consists of 3 stages :
Initiation
(Birth)
Propagation
(Growth)
Termination
(Death)
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15. CONT…
 Condensation Polymerization :
It involves a polymerization reaction between two
monomers with the expulsion of a simple by product .
A + B AB + Simple by product
It involves individual chemical reaction between reactive
mer .
By product is formed and condensed out .
This reaction is slower than additional polymerization.
Need reactive functional groups .
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16. CHARACTERISTICS OF POLYMER
 Low density
 Low coefficient of friction
 Good corrosion resistance
 Good mould ability
 Poor tensile strength
 Low mechanical properties
 Poor temperature resistance
 Can be produced transparent or different colours 16

17. APPLICATION
 Medicine : Many biomaterials especially heart valve
replacements and blood vessels are made up of polymers
like dacron , teflon .
 Consumer Science : Plastic containers of all shapes and
sizes are light weight and economically less expensive
than more traditional containers .
 Industry : Automobile parts , pipes , tanks , packing
material , adhesives are all polymer application used in
industrial market .
 Sports : Playground equipment , golf clubs , swimming
pools and protective helmets are produced from polymers.
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18. REFERENCES
 Robinson J R and Lee V H ; Controlled Drug Delivery –
Fundamentals and Applications ; Marcel Dekker .
 Jain N K ; Controlled and Novel Drug Delivery ; CBS
publication .
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