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melts.

2. Thermosetting Plastics:

 Thermoset plastics are hard and rigid.

 Thermoset can be moulded to set it in any shape but it cannot be remoulded.
 It is dark in colour, 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 used as a part of fibre glass sheet in the making of helmets.
 Some of the better known thermosetting plastics are Bakelite, Melamine and Teflon.

 The polymers in thermosetting plastics are arranged in a cross-linked form, where the
long polymer chains are cross-linked to each other. Therefore, on heating, these cross-links

prevent the displacement of individual polymer chains and does not get soft and melt.

Some Common Types of Plastics:

 Polythene: It is a plastic obtained by the polymerisation of a chemical compound known as
ethane. It is a thermoplastic.

 Polythene is tough and durable. So, it is used in making of polythene bags, waterproof
plastic sheets&bottles and also used for packaging.

 Polyvinyl chloride (PVC):It is a strong and hard thermoplastic.

 PVC is used in making of raincoats, seat covers, electric wires, pipes, etc.

 Bakelite: It is a hard and strong thermosetting plastic.

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