Question

Classify plastics on the basis of effect of heat on them. [2 marks]

Answer 1

Depending upon the effect of heat, plastic can be classified into two types.
$\bullet$ The plastic that can be moulded as per our wish is called as thermoplastic. eg. Polythene, PVC are used for manufacturing the toys, combs, plates, bowls etc. [1 mark]
$\bullet$ Another plastic is such that once a specific shape is given with the help of mould, its shape cannot be changed on heating. It is called as thermosetting plastic. eg. Electric switches, coverings over the handles of cookers, etc. [1 mark]