Question

Explain that vulcanised rubber is an elastomer.

Answer 1

On stressing elastomer, the polymer chain stretches, but due to cross linking tearing is prevented. On relieving the strain, the chain returns to its original position. Thus elastomers shows elasticity. Such polymers are stretchy.
During vulcanisation, natural rubber undergoes cross linking of cis-1,4 polyisoprene chains through disulphide bonds. This makes vulcanised rubber tough, elastic and stretchy. Hence, vulcanised rubber is an elastomer.