polymers, addition, and condensation polymerization

1. Plastic
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 Presented By
• Ganesh Sutar

2. Plastic
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•Plastic is a synthetic material
•polyethylene, PVC, nylon, etc.
•can be molded into shape.
•How plastics are prepared?
•What are polymers and monomers?

3. •Polymer : a long molecule formed by joining together of
thousands of small molecular units by chemical bonds.
•Monomer: Small molecules which combine together to
form polymer molecules are known as Monomers.
•Polymerization: The chemical process leading to the
formation of polymer is known as Polymerization.
Plastic

4. Properties of Plastic
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• Plastics are light, chemically stable
•Transparent and smooth.
• Corrosion resistance
• Low electrical and thermal conductivity, insulator
•Good insulation, low thermal conductivity.
•Light weight but posses good strength and rigidity.
•Low moisture absorption.
•Heat resistance.

5. Polymers: A polymer is a long molecule formed by joining together of
thousands of small molecular units by chemical bonds
Polymer and monomer
Poly=many,
Mere = parts or units or
molecules
mono =single
Mere = parts or units or
molecules

7. Homomer: In this type, a single type of monomer unit is present.
For example, Polyethene
Heteropolymer or co-polymer: It consists of different type of
monomer units.
For example, nylon -6, 6
Classification Based on
Monomers

8. Polymers classification on their
structure

9. 1. Natural polymers : Starch, Cellulose
2.Synthetic polymers: Plastics ,rubbers ,fibers.
On the basis of Occurrence :

10. are the polymers that become soft on heating and hard
on cooling and the process can be repeated for a number
of times.
They undergo reversible changes on heating.
Examples: Polythene (PE), polypropylene (PP), polyvinyl-
chloride (PVC),
1.Thermo softening Polymers

11. Thermo softening Polymers
Properties:
 are formed by addition polymerization
 consists of linear polymer chains
 are soft and less brittle.
 are soluble in organic solvents.
 are enable for molding into any shape.
 can be reheated and molded into any other
shape reversibly any number of times without
any change in the chemical nature.

12.  Thermosets are the polymers that undergo chemical
changes and crosslinking on heating and become
permanently hard, rigid and infusible.
 They will not soften on heating, Once they are set.
 Examples: Phenol-formaldehyde resin, urea-
formaldehyde resin, epoxy resins (araldite), melamine,
Bakelite
2.Thermosetting polymers

13. Thermosets (Thermosetting resins):
 are mostly formed by condensation polymerisation.
 are mostly branched polymer chains with potential
to form a 3- dimensional structure.
 become hard and rigid on heating during molding
process.
 are not soluble in common organic solvents.
 cannot be softened, reformed, reshaped once they
are set.
 cannot be reclaimed from wastes.
2.Thermosetting polymers

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Types of polymerization:
• I. Addition polymerization (or) chain polymerization
• II. Condensation or, step growth polymerization

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Addition polymerization
It is a process in which the monomers are repeated
addition , to forms a long chain polymers
 No molecule is elimination during polymerization
 Fast and exothermic process
 Require a catalyst
Ex: nCH2 = CH -------------- (CH2 – CH2)n

16. Addition polymerization

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Condensation polymerization
It is a process in which the monomers are repeated
joined or linked together forming a long chain polymer
with elimination of molecules.
 Molecule is elimination during polymerization
 Slow and endothermic process.
 May Require a catalyst

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Condensation polymerization

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Polyethylene
Polyethylene is the simplest of all commercial
polymers, and yet, it is the most popular plastic in the
world.
Properties:
1. It is a rigid, waxy, material
2. non-polar material
3. It has chemical resistance to strong acids, alkalis and
salts at room temperature.
4. Good insulator of electricity.
5. It is a branched polymer.

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Polyethylene
Applications:
• It is used as a film for packaging
food, clothing, and hardware.
• Most commercial trash bags,
sandwich bags, and plastic
wrapping are made from
polyethylene films.
• Polyethylene is also used for
everything from seat covers to
milk bottles, pails, pans, and
dishes.

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Polyvinyl chloride (PVC)
Preparation:

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1. It is odorless, colorless, chemically inert.
2. Insoluble in hot acids, alkalis ; soluble in hot
ethyl chloride.
3. Undergo degradation in the presence of heat
and light.
Polyvinyl chloride (PVC)
Properties:

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PVC known under different trade names – tygon,
vinylite, velon, geon.
1. Un plasticized PVC is used in pipes, tubes,
helmets, light fittings, automobiles mudguards.
2. Plasticized PVC is used in table cloths, curtains,
rain-coats, insulation of electric cables.
3. Healthcare components such as temporary blood
storage and dialysis devices.
Polyvinyl chloride (PVC)
Applications:

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TEFLON
Preparation : of Polytetrafloroethylene (PTEE) or
Teflon or Fluon

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Properties of Teflon:
1. High softening point (about 350̊ C)
2. High density
3. High thermal stability
4. High chemical resistance
5. Good electrical insulators
6. Mechanical properties do not change over prolonged
periods even at high temperature.

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Applications of Teflon
Applications:
1. Used for electrical insulation of wires and cables
2. Used in the making of non-stick frying pans,
stop cock for burettes.
3. Used as solid lubrication film.

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Epoxy resin
•Epoxy resin is defined as a molecule
containing more than one epoxide groups.
•The epoxide group also termed as, oxirane or
ethoxyline group.
•There are two main categories of epoxy
resins, namely the glycidyl epoxy, and non-
glycidyl epoxy resins.
•The glycidyl epoxies are further classified as
glycidyl-ether, glycidyl-ester and glycidyl-
amine.

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Preparation of Epoxy resin

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Properties of Epoxy resin
•They have excellent resistance to wear, they
are also tough and heat resistant.
•Being polar, they have excellent adhesive
characteristics.
• Low water absorption tendency, dimensional
stability, good heat and electrical resistance

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Applications of Epoxy resin
•Used for surface coating particularly for
making skid resistant surfaces for
highways, road junctions.
•Used as adhesives for glass, metals etc.
and popularly known as araldite.
•It is good material for electronic
applications.