Differentiate between rubbers and plastics on the basis of intermolecular forces.


 

Rubber is a natural polymer that possesses elastic properties. The natural polymer is a linear polymer of isoprene (2-methyl-1,3-butadiene).

In natural rubber, cis-polyisoprene molecules consist of various chains held together by weak van der Waals' interaction and have a coiling structure. So, it can be stretched like a spring.

Plastics are generally polymer of ethene known as polythene. Polythene is a thermoplastic polymer which may be linear (HDP) or branched (LDP) these type of polymers. Possesses intermediate intermolecular forces of attraction. It has a linear, structure that can be molded but can't be regained on its original shape after stretching.