Polymers

Rana zia ur rehman
Graduate Reseracher at KASIT (Korea Advanced of science & Technology)
My Email ID: [email protected]

3. CONTENTSCONTENTS
Introduction of polymer Introduction of polymer
History of polymerHistory of polymer
PolymerizationPolymerization
Classification of polymerClassification of polymer
Structure of polymerStructure of polymer
Types of polymerTypes of polymer
Properties of polymerProperties of polymer
Advantages of polymerAdvantages of polymer
Disadvantages of polymerDisadvantages of polymer
Uses of polymerUses of polymer

4. INTRODUCTION OF INTRODUCTION OF
POLYMERPOLYMER
Polymer is derived from two Greek words “poly” means many and Polymer is derived from two Greek words “poly” means many and
“meros” means part.“meros” means part.
Polymer is complex and giant molecule of higher molecular weight.Polymer is complex and giant molecule of higher molecular weight.
Polymer is also called macromolecule.Polymer is also called macromolecule.
Polymer is basically hydrocarbons.Polymer is basically hydrocarbons.
Polymer frequently containPolymer frequently contain
Nitrogen
Fluorine
Silicon
Sulfur
Chlorine

5. DEFINITION OF POLYMERDEFINITION OF POLYMER
A A polymerpolymer is a large molecule composed of small repeating is a large molecule composed of small repeating
structural units by the process of polymerization. Small repeating structural units by the process of polymerization. Small repeating
units are called monomers . These subunits are typically units are called monomers . These subunits are typically
connected by chemical covalent bonds.connected by chemical covalent bonds.

6. HISTORY OF POLYMERHISTORY OF POLYMER
 In 1811, Henri Braconnot did pioneering work on cellulose.In 1811, Henri Braconnot did pioneering work on cellulose.
 In the nineteenth century vulcanization is improved .In the nineteenth century vulcanization is improved .
 In 1907, Leo Baekeland created the first synthetic polymerIn 1907, Leo Baekeland created the first synthetic polymer
which is Bakelite .which is Bakelite .
In 1922, Hermann Staudinger proposed that polymers consisted In 1922, Hermann Staudinger proposed that polymers consisted
of long chains of atoms held by covalent bonds.of long chains of atoms held by covalent bonds.
Paul Flory did extensive work on addition polymerization, chain Paul Flory did extensive work on addition polymerization, chain
transfer and excluded volume.transfer and excluded volume.

7. POLYMERIZATIONPOLYMERIZATION
PolymerizationPolymerization is a process of reacting monomer molecules is a process of reacting monomer molecules
together in a chemical reaction to form three-dimensionaltogether in a chemical reaction to form three-dimensional
networks or polymer chains.networks or polymer chains.
There are two types of polymerizationThere are two types of polymerization
1. Addition Polymerization
2. Condensation Polymerization

8. ADDITION ADDITION
POLYMERIZATIONPOLYMERIZATION
A chemical reaction in which simple molecules (monomers) areA chemical reaction in which simple molecules (monomers) are
added to each other to form long-chain molecules (polymers).added to each other to form long-chain molecules (polymers).
 Free radical mechanism.Free radical mechanism.
 No Byproducts.No Byproducts.
 The catalyst used in addition polymerization is organic per The catalyst used in addition polymerization is organic per
oxide.oxide.
 Polymer formed during this process is chemically inert.Polymer formed during this process is chemically inert.
 Monomers contain C=C bondsMonomers contain C=C bonds

9. BASIC STEPS OF ADDITION BASIC STEPS OF ADDITION
POLYMERIZATION POLYMERIZATION
Initiation: Formation of free radicalInitiation: Formation of free radical
Propagation: Propagation: Combining of monomer to form chains Combining of monomer to form chains
Termination: Termination: Elimination of free radical Elimination of free radical
Addition Polymerization

10. CONDESATION CONDESATION
POLYMERIZATIONPOLYMERIZATION
A condensation polymerization occurs when a polymer is formedA condensation polymerization occurs when a polymer is formed
from a reaction that leaves behind a small molecule, often water.from a reaction that leaves behind a small molecule, often water.
The formation of peptide bonds in proteins is an example of aThe formation of peptide bonds in proteins is an example of a
condensation polymerization.condensation polymerization.
Byproducts produced.Byproducts produced.
They have high melting point.They have high melting point.
The byproduct eliminated is called as condensate.The byproduct eliminated is called as condensate.

11. CLASSIFICATION OFCLASSIFICATION OF
POLYMERSPOLYMERS
POLYMERPOLYMER
Inorganic polymerOrganic polymer
Natural polymerSynthetic polymer

12. NATURAL POLYMERSNATURAL POLYMERS
The polymers which are found naturally is called natural Polymer. The polymers which are found naturally is called natural Polymer.
Natural polymers tend to be readily biodegradable.Natural polymers tend to be readily biodegradable.
All living things plants, animals, and people are made of polymers. All living things plants, animals, and people are made of polymers.
Natural polymers are:Natural polymers are:
CelluloseCellulose
 StarchStarch
 LigninLignin
 ProteinProtein
 RubberRubber
 Nucleic acidNucleic acid
 CarbohydratesCarbohydrates

13. PROTEINS PROTEINS

Proteins are polymers made out of amino acids. They're naturally Proteins are polymers made out of amino acids. They're naturally
occurring, meaning they're made by animals, plants, bugs, fungi, occurring, meaning they're made by animals, plants, bugs, fungi,
and other living things. So, proteins are polymers of amino acidsand other living things. So, proteins are polymers of amino acids
Amino acids have an amino end and an
acid end. In the middle is a C (carbon)
with an H (hydrogen) and a side group
shown here as an R.

14. SYNTHETIC POLYMERSSYNTHETIC POLYMERS
Synthetic polymers is a polymer that is manufactured in industrySynthetic polymers is a polymer that is manufactured in industry
from chemical substances through the polymerization process.from chemical substances through the polymerization process.
Man made polymers are called Synthetic polymer.Man made polymers are called Synthetic polymer.
Synthetic polymers are:Synthetic polymers are:
Nylon
Polyester
Polyethylene
PVC
Polycarbonate
Epoxy Resins
Polystyrene
Polypropylene
Teflon

15. NYLON 6-6NYLON 6-6
Nylon 6-6 is a synthetic polymer which is formed by theNylon 6-6 is a synthetic polymer which is formed by the
condensation polymerization of hexamethylenediamine andcondensation polymerization of hexamethylenediamine and
adipic acid.adipic acid.
It is called Nylon 6-6 because each repeat unit of the polymerIt is called Nylon 6-6 because each repeat unit of the polymer
chain has two stretches of carbon atoms; each is six carbonchain has two stretches of carbon atoms; each is six carbon
atoms long. atoms long.
nHOOC-(CH
2
)
4
-COOH+n H
2
N-(CH
2
)
6
-NH
2
---->[-OC-( CH
2
)
4
-CO-NH-(CH
2
)
6
-NH-] n+2nH
2
O
1,6 DiaminohexaneAdipoly chloride Nylon 6-6
Nylon-6.6 are mainly used as fibers for clothing and also
other hard parts in light engineering.

16. STRUCTURE OF POLMERSSTRUCTURE OF POLMERS
1-Linear chain structure:1-Linear chain structure:
These are formed when chains are built up without anyThese are formed when chains are built up without any
deviation. They are generally formed when the monomers useddeviation. They are generally formed when the monomers used
have only two reactive sites.have only two reactive sites.
2-Branched chains structure:2-Branched chains structure:
Deviation can occur when the chain is being formed andDeviation can occur when the chain is being formed and
chain branching can result.chain branching can result.
3- Cross-linking structure:3- Cross-linking structure:
The branches can join up to give cross-links betweenThe branches can join up to give cross-links between
adjacent chains.adjacent chains.
Cross-link CHAIN Linear chain polymer

17. TYPES OF POLYMERSTYPES OF POLYMERS
Types of polymers based on monomersTypes of polymers based on monomers
Types of polymers based on thermal propertiesTypes of polymers based on thermal properties

18. TYPES BASED ON MONOMERSTYPES BASED ON MONOMERS
Homo polymerHomo polymer::
A polymer which is obtained by the polymerization of only oneA polymer which is obtained by the polymerization of only one
type of monomer is known as a homopolymer e.g. Teflon,type of monomer is known as a homopolymer e.g. Teflon,
polyethylene polyethylene
A + A + A + A A + A + A + A  -A-A-A-A- -A-A-A-A-
CopolymerCopolymer: :
When two different types of monomers are joined in theWhen two different types of monomers are joined in the
same polymer chain, the polymer is called a copolymersame polymer chain, the polymer is called a copolymer e.g.e.g.
polyamides ,polyesters.polyamides ,polyesters.
A + B + A + BA + B + A + B -A-B-A-B- -A-B-A-B-

19. TYPES BASED ON THERMAL TYPES BASED ON THERMAL
PROPERTIESPROPERTIES
ThermoplasticThermoplastic
ThermosetsThermosets

20. THERMOPLASTICTHERMOPLASTIC
A polymer that soften or melt when heated and harden whenA polymer that soften or melt when heated and harden when
Cooled.Cooled.
No cross links between chains.No cross links between chains.
Weak attractive forces between chains broken by Weak attractive forces between chains broken by warmingwarming..
Weak forces reform in new shape when cold Weak forces reform in new shape when cold
Recycle ableRecycle able
Only Secondary bonds between the molecules.Only Secondary bonds between the molecules.
Examples are Examples are polyethylene, polypropylene, polystyrene, polyethylene, polypropylene, polystyrene,
polyester, polyvinyl chloride, acrylics and nylons.polyester, polyvinyl chloride, acrylics and nylons.
Thermoplastic

21. THERMOSETSTHERMOSETS
Thermoset polymers are synthetic materials that strengthenThermoset polymers are synthetic materials that strengthen
during being heated but cannot be successfully remoldedduring being heated but cannot be successfully remolded..
Extensive cross-linking formed by covalent bonds.Extensive cross-linking formed by covalent bonds.
Bonds prevent chains moving relative to each other. Bonds prevent chains moving relative to each other.
Cannot be reshapedCannot be reshaped
Not recycle ableNot recycle able
Primary and secondary both types of bonds are presentPrimary and secondary both types of bonds are present..
They retain their strength and shape even when heated.They retain their strength and shape even when heated.

22. PROPERTIES OF POLYMERSPROPERTIES OF POLYMERS
Physical properties of polymersPhysical properties of polymers
Mechanical properties of polymersMechanical properties of polymers

23. PHYSICAL PROPERTIESPHYSICAL PROPERTIES
The physical properties of a polymer, such as its strength The physical properties of a polymer, such as its strength
and flexibility depend on:and flexibility depend on:
Chain lengthChain length - in general, the longer the chains the - in general, the longer the chains the
stronger the polymer;stronger the polymer;
Side groupsSide groups - polar side groups give stronger attraction - polar side groups give stronger attraction
between polymer chains, making the polymer stronger;between polymer chains, making the polymer stronger;
BranchingBranching - straight, unbranched chains can pack - straight, unbranched chains can pack
together more closely than highly branched chains, giving together more closely than highly branched chains, giving
polymers that are more crystalline and therefore stronger;polymers that are more crystalline and therefore stronger;
Cross-linkingCross-linking - if polymer chains are linked together - if polymer chains are linked together
extensively by covalent bonds, the polymer is harder and extensively by covalent bonds, the polymer is harder and
more difficult to melt.more difficult to melt.

24. MECHANICAL PROPERTIES OF MECHANICAL PROPERTIES OF
POLYMERSPOLYMERS
Tensile StrengthTensile Strength
ElongationElongation
Modulus of elasticityModulus of elasticity
ToughnessToughness

25. TENSILE STRENGHT OF TENSILE STRENGHT OF
POLYMERSPOLYMERS
The tensile strength of a material is the maximum amount ofThe tensile strength of a material is the maximum amount of
tensile stress that it can take before failure.tensile stress that it can take before failure.
Critical length needed before
strength increases.
Hydrocarbon polymers average of
100 repeating units necessary but only
40 for nylons.
Tensile strength measures the forces
needed to snap a polymer.
When modulus of elasticity is
increases strength is also increases.

26. ELONGATIONELONGATION
The change length over original length is called elongation.
 When the elongation is high , material is elastic.
 When the elongation is low, material is called brittle.
Elongation is a type of deformation.
 Deformation is simply a change in shape
that material undergoes under stress.
There are two important types of elongation:
Ultimate elongation
Elastic elongation

27. MODULUS OF ELASTICITY MODULUS OF ELASTICITY
Stress over strain ratio is called modulus of elasticity.Stress over strain ratio is called modulus of elasticity.
The stress on a material increases then strain is also producedThe stress on a material increases then strain is also produced
in a material until the material break down. The graph we drawin a material until the material break down. The graph we draw
is called stress-strain curve.is called stress-strain curve.
Modulus is expressed in Modulus is expressed in
the same units as strength,the same units as strength,
such as N/cmsuch as N/cm
22
..
Modulus of elasticity = stress/strain

28. TOUGHNESSTOUGHNESS
Toughness is really a measure of the energy a material canToughness is really a measure of the energy a material can
absorb before it breaks.absorb before it breaks.
The area underneath the stress-strain curve is also calledThe area underneath the stress-strain curve is also called
Toughness.Toughness.
When modulus of elasticity increases, toughness isWhen modulus of elasticity increases, toughness is
decreasing.decreasing.
When modulus of elasticity is moderate, When modulus of elasticity is moderate,
the material have both toughness and strength. the material have both toughness and strength.

29. ADVANTAGES OF POLYMERSADVANTAGES OF POLYMERS
 Low densityLow density
 Low absolute strength Low absolute strength
 StiffnessStiffness
 Ultra durableUltra durable
 Resistance to corrosionResistance to corrosion
 Thermal electrical insulatorThermal electrical insulator
 FlexibleFlexible
CheaperCheaper
 RecyclableRecyclable

30. DISADVANTAGES OF POLYMERSDISADVANTAGES OF POLYMERS
 Low density
 Non bio-degradable
 Easily breakable
 Flame retardancy is low
 When polymers incorporated with additives are burnt they
emit a lot of poisonous gases into the atmosphere
 Low molecular weight polymers (Polyethylene bags) are
difficult to recycle
 Improper disposal leads to environmental pollution

31. USES OF POLYMERSUSES OF POLYMERS
BIO POLYMER USESBIO POLYMER USES
NON BIO POLYMER USESNON BIO POLYMER USES

32. BIO POLYMER USESBIO POLYMER USES
STARCHSTARCH
1- 1- POTATO IS THE MAIN SOURCE OF STARCHPOTATO IS THE MAIN SOURCE OF STARCH
2- STARCH IS ALSO PRESENT IN RICE2- STARCH IS ALSO PRESENT IN RICE
3- MAIZE(CORN) 3- MAIZE(CORN)

33. CELLULOSECELLULOSE
Uses of cellulose acetateUses of cellulose acetate
Musical instrumentsMusical instruments
Automobile steering wheelsAutomobile steering wheels
Uses of cellulose nitrateUses of cellulose nitrate
Used for making tooth brushesUsed for making tooth brushes
Used for making, pencils, combs, buttons, etcUsed for making, pencils, combs, buttons, etc
:

34. USES OF NON-BIOPOLYMERSUSES OF NON-BIOPOLYMERS
PolypropylenePolypropylene::
Used in making ropes, carpets, blankets, hand bags, etcUsed in making ropes, carpets, blankets, hand bags, etc
Used for making water pipes, washing machine parts.Used for making water pipes, washing machine parts.
Polystyrene:Polystyrene:
Used in the manufacture of jars, bottles, toys, etcUsed in the manufacture of jars, bottles, toys, etc
Refrigerator insulationRefrigerator insulation

35. Epoxy resins:
Used in industrial flooring
Used as good adhesives
Used in glass fiber, reinforced plastics
Polyester resin:
Used for making synthetic fibers
Used for making coat insulation, conveyor belt

36. Polyethylene terepthalates
Soft drink bottles
Non-breakable bottle
Uses of polyolefin in daily life:
Furniture
Carpeting
Electrical insulation
Uses of polyvinyl chloride in daily life
Water pipe
Phonograph record