Question

Which of the following are characteristics of thermosetting polymers?

(i) Heavily branched cross linked polymers.

(ii) Linear slightly branched long chain molecules.

(iii) Become infusible on moulding so cannot be reused.

(iv) Soften on heating and harden on cooling, can be reused.

Answer 1

(i) Heavily branched cross linked polymers.

(iii) Become infusible on moulding so cannot be reused.

Explanation:

Thermosetting polymers are cross linked or heavily branched molecules, which on heating undergo extensive cross-linking in moulds and again become infusible. These cannot be refused.