Which of the following polymers are thermoplastic?
(b) Natural rubber
Answers: (a). Teflon and (d). Polystyrene
(i) These are linear or slightly branched long chain molecules.
(ii) These polymers are hard at room temperature, become soft and viscous on heating and again rigid on cooling. This process of heat softening and hardening on cooling can be repeated as many times as desired without any change in chemical composition.