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The clothes which we wear are made of fabrics. Fabrics are made fromfibres obtained from natural or artificial sources. Fibres are also used formaking a large variety of household articles. Natural fibres like cotton,

wool, silk, etc., are obtained from plants or animals. The synthetic fibres,on the other hand, are made by human beings. That is why these arecalled synthetic or man-made fibres..

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Look at the uniform pattern found in the necklace of beads joined with

the help of a thread and a number of paper clips joined together to

make a long chain.

A synthetic fibre is also a chain of small units joined together. Each small

unit is actually a chemical substance. Many such small units combine to

form a large single unit called a polymer . The word ‘polymer’ comes from

two Greek words; poly meaning many and mer meaning part/unit. So, a

polymer is made of many repeating units.

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1. RAYON

2. NYLON

3. TERYLENE

4

. POLYETHENE TETRAPHTHALATE (PET)

5. ACRYLIC FIBRES (ACRYLON)

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Towards the end of the nineteenth century, scientists were successful in

obtaining a fibre having properties similar to that of silk. Such a fibre was

obtained by chemical treatment of wood pulp. This fibre was called rayon or

artificial silk. Although rayon is obtained from a natural source, wood pulp, yet it

is a man-made fibre. It is cheaper than silk and can be woven like silk fibres. It

can also be dyed in a wide variety of colours. Rayon is mixed with cotton to

make bed sheets or mixed with wool to make carpets.

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Nylon is another man-made fibre. In 1931, it was made without using any natural rawmaterial (from plant or animal). It was prepared from coal, water and air. It was thefirst fully synthetic fibre. Nylon fibre was strong, elastic and light. It was lustrous andeasy to wash. So, it became very popular for making clothes. We use many articlesmade from nylon, such as socks, ropes, tents, toothbrushes, car seat belts, sleeping

bags, curtains etc. Nylon is also used for making parachutes and ropes for rockclimbing. A nylon thread is actually stronger than a steel wire.

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Terylene fabric is a synthetic polyester fibre based on terephthalic acid.It is characterised by weightlessness and crease resistance. Terylene ismostly used for clothing, ropes, sheets, sails and many others. The name

'terylene fabric' may also refer to any large class of synthetic fabric.

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It's a plastic resin and the most common type of polyester. Twomonomers—modified ethylene glycol and purified terephthalicacid—are combined to form the polymer called polyethyleneterephthalate.

Many beverages, food items and other consumer products aredelivered in bottles or packages made from PET. The #1 code is

usually found on or near the bottom of the container.It's safe, strong, transparent and versatile. Customers choose itfor its safety, light weight, resealability, shatter-resistance andrecyclability. Up to 100% of a PET package can be made fromrecycled PET, and the material can be recycled again and again.

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Acrylic fabric is a type of fabric made from acrylic fibres, and was

first manufactured by the DuPont Company. It uses a chemically

produced substance called acrylonitrile, which is also used in the

production of plastics. Acrylonitrile tends to break down easily in

the environment. Acrylic fabric is used widely in knits,

as upholstery covering, and the fibres may be woven to make rugs.

People often think of acrylic fabric as an excellent wool substitute,and certain forms of it are exceptionally soft, while remaining light

weight.

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Uses of

acrylic

Acrylic knittingwool is good for

baby wears

because they aresoft, warm andwashable.

Used for makingartificial fur,blankets,

carpets etc.

A transparenttype of acrylic isused to cover

automobilelights, lensessurgical tools

etc

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Synthetic fibres burnmore readily than natural. Prone to heat damage,

they melt relatively easily. Prone to damage by hot washing. More electrostatic

charge is generated byrubbing than with naturalfibres.

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Plastic is also a polymer like the synthetic fibre. All plastics do not have thesame type of arrangement of units. In some it is linear, whereas in others it iscross-linked. [(a)Linear (b)Cross linked arrangements.] Plastic articles areavailable in all possible shapes and sizes. Plastic is easily mouldable i.e. can beshaped in any form. Plastic can be recycled, reused, coloured, melted, rolled

into sheets or made into wires. That is why it finds such a variety of uses.

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A lighter world with

plastics! Plastics can even helpyou conserve your ownenergy! Plasticpackaging meanslighter shopping to carryhome.

A cosier world with plastics! When properly installed, plasticinsulation can cut heat or coldloss at home or school by up to70%, making it so much warmeror cooler, cosier and energy-efficient!

Capture the wind’s power with plastics! Wind power is free but did you knowthat capturing the power of the windwould be impossible without plastics?Special plastics are used in the windturbine covers and huge blades to tap

into this environmentally friendly energysource!

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Flying further on less fuel with plastics! Did you know that plastics are being used to replacemore and more aircraft parts? The wing boxes of theAirbus A380 use plastic fibre composites, whichreduces the aircraft by 1.5 tons. The aircraft can flyfurther and carry more cargo using the same amount

of fuel, talk.

Lighter cars with plastics! Plastic is an ideal material for use in carmanufacturing. A modern mid-range car containsabout 11% plastic material components. Thatmeans less weight, less fuel consumption andtherefore less CO2 emissions.

Tapping the sun’s energy with plastics! Did you know that harnessing solar powerwould be impossible without plastics? Solarpanels are made from plastics, and solarpower is a free, highly efficient energy source!

Plastic packaging saves fuel! Did you know that the amount of fuel adelivery truck needs could be considerablyreduced if the cargo uses plastic containers?Obvious: lightweight means less fuelconsumption!

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Switch off the engine with plastics! Using plastic to exploit the power ofthe wind can reduce a ship’s fuelconsumption considerably, whichmeans lower oil consumption and lessCO2emissions!

Keeping it cool with plastics! Today’s refrigerators use plastics intheir insulation systems to ensurethat your food and drinks stayfresher and cooler for longer whilstusing less energy!

More light for less energy! Innovative technology and specialplastic lenses used in today’s LEDsmeans that they are twice as brightas conventional types using thesame amount of energy!

A better world with plastics!Did you know that we use plastics to keepour homes warmer, our cars lighter and ourfood fresher? Plastics are also used to harnesswind and solar energy resources cleanly andefficiently!

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Types ofplastics

Thermosets thermoplastics

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Thermoset plastics

Thermoset plastics are hard and rigid. Example is Bakelite

and melamine. Thermoset can be moulded to set it in any

shape but it cannot be remoulded. It is dark in color, hard

and resistant to heat and electricity. It is being widely used for

the handle of kettles and pans. Earlier black telephone sets,

electric switches, electric lamp holders, pins and plugs were

made from thermoset plastic. It is also being used as a part of

fibre glass sheet in the making of helmets. Melamine is a kind

of Thermoset plastics used in good quality tableware.Melamine is also used as a coating on uniforms of firemen to

make them fire resistant

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Thermoset handles

A firemans uniform is coated withthermoset plastic to made it fire resistant

Melamine wares

An electric pin (black)

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Thermoplastics

Thermoplastics are soft and flexib;e through they are

not elastic like rubber and steel springs. They melt on

warming and regain their shape on cooling.

Thermoplastics can be drawn into fine fibers,moulded to any desired shape or stretched or spread

as sheets. Some of the better known thermoplastics

are nylon (polyamide), polyesters, polyethylene,

polyvinyl chloride (PVC), acrylic, polyurethane,polypropylene (PP), poly-tetra-fluoro-ethylene (PTEE)

etc

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Plastic table and chairs

Plastic food containers

Plastic toys

Plastic spoons and forks

Plastic cups

Plastic daily use items

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When we go to the market, we get usually things wrapped in plastic or packed inpolythene bags. That is one reason why plastic waste keeps getting accumulatedin our homes. Ultimately, plastic finds its way in the garbage. Disposal of plasticis a major problem. A material which gets decomposed through naturalprocesses, such as action by bacteria, is called biodegradable. A material which

is not easily decomposed by natural processes is termed as non-biodegradable.

Type of wasteApproximate time taken to

degenerateNature of material

Peels of vegetable and fruits,

leftover foodstuff, etc.1 to 2 weeks. Biodegradable

Paper 10 –30 days BiodegradableCotton cloth 2 to 5 months Biodegradable

Wood 10 to15 years Biodegradable

Woollen clothes About a year Biodegradable

Tin, aluminium, and other

metal cans100 to 500 years Non-Biodegradable

Plastic bags Several years Non-Biodegradable

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Plastic is a commodity that is consumed on a large-scale all around the world. Theproduction as well as disposal of plastic, pose a great threat to all the life forms onearth. This material takes years to discompose, which is one of the factors that killmany animals in water as well as on land. During the manufacture of plastic, manyhazardous chemicals are emitted which has resulted into dreadful disorders anddiseases in humans. Ethylene oxide, xylene and benzene are some of the chemicaltoxins present in plastic that has miserable effects on the environment.Read more at Buzzle.

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We should avoid the use of plastics as far as possible. Make use of bags made of

cotton or jute when you go for shopping. The biodegradable and non-

biodegradable wastes should be collected separately and disposed off separately.

Practise this in your homes. It is better to recycle the plastic waste. Most of thethermoplastics can be recycled. Make a list of items that can be recycled.

However, during recycling certain colouring agents are added. This limits its

usage especially for storage of food. As a responsible citizen remember

the 4R principle. Reduce, Reuse, Recycle and Recover . Develop habits which

are environment friendly.

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