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CHAPTER 7

SYNTHETIC MATERIALS ININDUSTRY

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Synthetic polymers

Chemical compounds that contain long-chainedmolecules of monomers.

Known as artificial polymers

Man-made polymers made up of chemicalsubstances from petroleum.

Used to make a wide range of products includingcomputers, fabrics, toys, furniture and electrical

parts.

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Can be clasified into;

1) Elastomers

2) Thermoplastic

3) Thermoset.

Thermoplastic and thermosets are plastics.

Synthetic polymers and their uses; Plastic- used in manufacturing industries of plastic

product.

Synthetic rubber- contain properties similar to a

natural rubber. Examples= neoprene, Styrene butadiene rubber

SBR

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Synthetic rubber is mostly used to make vehiclestyre.

Synthetic fibre is a type of polymer that hasproperties similar to natural fibre.

Example= nylon, terylene

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Synthetic rubber Properties Product

neoprene Does not burn

easily,high

restance to

oxygen, sunlight

Gloves, rubber

pipes

Styrene

butadiene rubber

(SBR)

Can be

vulcanised easily

Car tyres, shoe

sole

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Plastics

A type of synthetic polymer

Can be moulded and designed into various

products when heated up

An organic material that consists of carbon,hydrogen and a few other elements such as

oxygen, nitrogen, chlorine and flourine.

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Types of plastics

Two main types;1. Thermoplastic

2. Thermoset

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Thermoplastic

Thermoplastic molecules do not have cross

linkage between their polymers.

When heated up their polymer chains glide easilyonto each other.

This property makes thermoplastic a materialthat easily softens or melts and can beremoulded,

Therefore, thermoplastic can be easily recycled.

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Polymer chains in

thermoplastic

Examples; Polystyrene, polyvinyl chloride, perspex and

polythene

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Properties

Good insulator

Stretchable and

Burned easily

Low melting point

Dissolve in organicsolvent

Resistant to chemical

substances

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Thermoset

Thermoset molecules have cross linkagesbetween their polymers

These cross linkage prevent polymer chain

from gliding onto each other when heated. Can be moulded only once.

Examples of thermosets are bakelite,melamine.

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Exercise

Classify the following products as thermoplasticor thermoset;

Battery box, hanger, chair, water pipe,

electric plug, milk bottle, electrical switch.

Plastic

product

Thermoplastic Thermoset

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Potential uses of plastic

Plastic properties such as resistance to corrosion,hot hazardous to the body, clean, long lasting,

strong and can be produced in various shape are

the reasons why it is widely used in various field.

Hundreds of different plastics have been created

to replace metals, paper, wood and stone, glass

and ceramics.

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Plastic used in medical

fielda) Replace faulty heart arteries and valves.

b) Replaced damaged bones

c) To make thread to stitch wounds and tomake medicine capsules

d) Rebuild facial structure

e) To make camera pills to snap pictures ofinternal organs.

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Car parts are made of plastics such asbumpers, windscreen, steering, petrol cover,

and fan. Plastic are also used to make pans of cars and

aircraft and also bulletproof glass.

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Effect of plastic waste

disposal on the environment Burning of plastic products

Release pollutants that threaten health and theseinclude;

black smoke

Smelly and poisonous gases, corrosive gases thatinclude hydrogen chloride, carbonmonoxide,ammonia and hydrogen cyanide

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Disposal of plastic products

Cause flash floods during heavy rain.

Plastic bags that are thrown into the sea will

cause pollution

Sea creatures like turtles will die when theyswallow plastic products

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Ways to control plastic

disposal1) Use biodegradable plastic that can be degrade bymicroorganism

2) Recycling plastic product

3) Reused tyres as artificial reefs, that will providebreeding space for marine lifes

4) Burn plastic waste in incinerator

5) Plastic waste materials can be collected, crushed andburied in a special dumping ground

6) Use photodegradation plastic.

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What can you do to help?

Choose products with minimal packaging

Reduce the need to throw away plastic.

Reuse plastic to carry things

Donate toys to charity

Sort garbage according to categories.