Synthetic Fibres and Plastics

Units

Natural fibre ,e.g.: cotton, wool, silk and synthetic fibre, e.g: rayon, nylon, polyester

Fibres made by human being or man- made fibres are called synthetic fibres

A synthetic fibre is a chain of small units that is actually a chemical substance. Many such chemical substance joined together to form a large single unit is called polymer.

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Rayon is known as artificial silk because its properties are similar to that of silk. It is obtained from wood pulp, yet it is man-made fibre and is cheaper than silk.

Source of rayon is wood pulp which is a natural source yet it is a man – made fibre.

Nylon is a man- made fibre which is prepared from coal, water and air. It was the first fully synthetic fibre.

Nylon fibre is strong, elastic and light

Socks, ropes, tents, bags, curtains, parachute etc.

Wrinkled

Terylene and PET

b - sweater

When synthetic fibres catch fire, it melts fastly and sticks to the body of the person wearing it. Thus we should avoid synthetic clothes while working in the kitchen or in a laboratory.

All the synthetic fibres are prepared by a series of process using raw materials that are of petroleum origin which are called as petrochemicals.

Plastics are non-reactive; they are light, string and durable. Plastics are poor conductors of heat and electricity.

Glass, buckets, chairs, ropes, covering of electrical wires, containers etc.

Polythene and PVC

Bakelite and melamine

Melamine

Plastics are light weighted, cheaper than other fabrics, strong and easy to handle, thus we prefer plastic containers for storage of items like water, milk, pickles, dry food

Heat and electricity

Teflon is a special kind of plastic on which oil and water do not stick and because of this property teflon is used for non-stick coating on cookwares for preparing non-stick cookwares.

Melamine is called fire proof plastic as it can resist fire and can tolerate heat better than other plastics, and because of this property of melamine it is used as coating of fireman’s uniforms.

Biodegradable is commonly associated with environmental friendly products that are capable of decomposing back into natural elements by natural processes such as action of bacteria. E.g. Paper, cotton cloth, wood etc.

Non- biodegradable is commonly associated with non- environmental friendly products that are not capable of decomposing back into natural elements easily by natural processes such as action of bacteria. E.g. plastic bags, tin aluminium and other metal cans.

Biodegradable

We should use cotton or jute bags while going for market to minimise the use of plastic bags, as they are non-biodegradable and not environmental friendly.

Because of very important property of plastic that is it can be easily mouldable and shaped in any form.

No. Only thermoplastics like polythene and PVC can bend easily while the thermosetting plastics like Bakelite and melamine does not get bend easily rather they break when forced to bend.

Thermoplastics are used for manufacturing toys, combs and various types of containers, and thermosetting plastics are used for making electrical wire, electrical switches, and handles of cooking utensils, floor tiles, cookwares and fabrics which resist fire.

Rayon

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Cotton plants.