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Published on Aug 26, 2012
PLASTICS: Plastics are polymers of chemical units which are linked together. These chemical units can be linked in two arrangements namely, linear arrangement and cross linked arrangement. Polythene is a linear polymer which consists of ethylene units linked together. Plastic articles like chairs, toys, buckets and mugs are household items used in day to day life. All these articles are of different shapes and sizes. This is due to property of plastics to be easily moldable. They can be reused and recycled into wires, pipes and other important materials. But all plastics cannot be bent or molded to change their shape. Some plastics deform on heating and some don't. The plastics which deform on heating are known as thermoplastics and those that don't are known as thermosetting plastics. Polythene and PVC are examples of thermoplastics. They are used in the manufacture of plastic bags and cable wires. Bakelite and melamine are examples of thermosetting polymers. Bakelite is a bad conductor of electricity and is used in the making of electric switches. Melamine is a versatile polymer and is a bad conductor of heat. It can resist fire better than any plastic. It is used in the manufacture of tiles, kitchenware and fibers that can resist heat. Plastic items are used mainly to store food items in houses.