SYNTHETIC FIBRES AND PLASTICS

 SYNTHETIC FIBRES AND PLASTICS

SYNTHETIC FIBERS

 Synthetic fibers are man-made fibers prepared from a chemical substance such as petrochemicals, so they are also known as man-made fibers. Synthetic fibers are generally polymers(polymers are the large single unit (large molecules) formed by joining repeated small unit( monomer) as a chain)

TYPES OF SYNTHETIC FIBERS

RAYON

    Rayon is a synthetic fiber obtained from the chemical treatment of wood pulps. It is also known as artificial silks because its property is similar to that of silk. 

PROPERTIES AND USES

1. It is cheaper than silk and can be woven like silk fabric
2. it can be dyed in various colours
3. it can be mixed with cotton to make bedsheets
4. it can be mixed with wool to make carpets

NYLON

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

PROPERTIES AND USES

1. it is strong, elastic, light, lustrous and easy to wash, so it is used widely to make cloths
2. it is used to make socks, rope, toothbrush, tends, car seat belts, sleeping bag, curtains etc
3. it is also used to make parachutes and rock climbing ropes
4. nylon thread is actually stronger than steel wires

POLYESTER

 Polyester is a synthetic fibre made up of the repeating units of chemical called esters.Terylene and pet are examples of polyester.

PROPERTIES AND USES

1. Fabric made up of these fibers does not wrinkle, remains crisp, easy to wash etc so it us used to make dress materials
2. Also used to make bottles, utensils, films, wires etc

ACRYLIC

 Acrylic fabrics are made up of synthetic polymers called acrylonitrile. They resemble as that of wool.

PROPERTIES AND USES

1. It resembles the natural wool but relatively cheaper than natural wool 
2. they are available in varieties of colours 

CHARACTERISTICS OF SYNTHETIC FIBERS

• Synthetic fibers are cheaper than natural fiber
• Synthetic fibers are stronger than natural fiber
• Synthetic fibers are more durable than natural fibers
• They dry up in less time
• They are easy to maintain and wash

PLASTIC

Plastic is a polymer where the units are arranged either as a liner or cross-linked polymers. It can be easily moulded to any shape.

TYPE OF PLASTIC

THERMOPLASTIC

A type of plastic which gets deformed easily on heating and can be bend easily is known as thermoplastic.

eg: polythene, polyvinyl chloride(PVC)

THERMOSETTING PLASTIC

A type of plastic which when moulded once cannot be softened on heating is known as thermosetting plastic

eg: Bakelite, melamine

NOTE:- Bakelite is a poor conductor of heat and electricity, so it is used for the making electrical switch, handles of various cooking utensils etc. Melamine can resist fire and can tolerate heat better than other plastic so it is used to prepare kitchen wares, fabric which can resist fire, floor tiles etc

CHARACTERISTIC PROPERTIES OF PLASTIC

1. PLASTIC IS NON-REACTIVE:-Plastic does not react with air and water. They don't corrode easily so they are used to storing various kinds of materials including chemicals
2. PLASTIC IS LIGHT, STRONG AND DURABLE:- Plastic is light, strong and durable can be moulded into different shapes and sizes, so it is used for various purposes they are cheaper than metals
3. PLASTIC ARE POOR CONDUCTORS:- Plastic are poor conductors of heat and electricity so they are used to make coverings of electrical wires, handles of screwdrivers, handles of frying pans etc

 NOTES

• Plastic is used in the medical industries for packing tablets, tread used for switching wounds syringes, gloves etc.
• special cookware is used for cooking food in microwave ovens 
• Teflon is used as a non-stick coat on cookware's in which oil and water does not stick
• Melamine is fireproof plastic used for coating uniforms of fireman make them flame-resistant

PLASTIC AND ENVIRONMENT

Plastic is not an environment-friendly material. It is non-biodegradable it takes several years to degenerate burning of plastic material releases a lot of poisonous gas to the atmosphere causing air pollution. Dumping plastic improperly cause several environmental problems  such as

• clogging of the drain
• while eating food wastes animals swallow materials like polythene bags may result in their death
• pollute the soil and also pollute the air when burned

As a responsible citizen, we have to reduce the use of plastic as far as possible. Some measures to reduce the usage of plastics are

• use bags made up of cotton or jute for shopping
• biodegradable and non-biodegradable wastes should be disposed of separately 
• reuse and recycle plastic products
• follow 5R principle(reuse, reduce, recycle, recover and refuse)