Nowadays, plastic becomes an essential part of our daily life. However, plastic world market is growing very fast as compare to any other market of the world.
The word plastic is derived from the Greek word "plastikos" meaning capable of being shaped or molded, from plastos meaning molded.It refers to their malleability, or plasticity during manufacture, that allows them to be cast, pressed, or extruded into a variety of shapes—such as films, fibers, plates, tubes, bottles, boxes, and much more.
What is plastic?
Plastic is a common name for Polymers: materials made of long strings of carbon and other elements. Each unit in a string is called a monomer, and is a chemical usually derived from oil.
The monomer is made into polymer by chain-linking reactions. This is like making a daisy chain. Instead of flowers, carbon atoms are joined together. The appearance of the daisy chain will be different if you use different coloured flowers, and so will polymers.
There are many different types of plastic, depending on the starting monomer selected, the length of polymer chains, and the type of modifying compounds added. Each plastic has been developed for a special purpose.
There are two main groups of plastics:
1. THERMOPLASTICS soften with heat and harden with cooling.
* Some typical thermoplastics are: Acrylic (Perspex)
* Acrylo-nitrile (Nylon)
* Polyethylene (Polythene)
* Polypropylene
* Poly Vinyl Acetate (PVA)
* Poly Vinyl Chloride (PVC)
* Polystyrene and ABS
* PTFE (Teflon)
2. THERMOSETS are cured or hardened by heat.
Some typical thermosets are:
* Bakelite
* Epoxy
* Melamine
* Polyester
* Polyurethane
Properties
Plastics are used because they are:
* Attractive
* Hard and slippery
* Soft and rubbery
* Tough and slippery
* Flexible
* Good insulators of heat or electricity
* Light weight
* Hygienic
* Non-rusting
* Easy to shape and colour
* Cheap
The tremendous growth of the plastics industry is expected to continue..The factors that have contributed to this growth include the energy efficiency of plastic world market. All studies show that it takes less energy to make a product from plastics than just about any other material.
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