Question

In vulcanisation of rubber,

• A. sulphur reacts to form new compound
• B. sulphur cross links are introduced
• C. sulphur forms a very thin protective layer over rubber
• D. All of the above.

Answer 1

Answer: (B)

sulphur cross links are introduced

In vulcanisation of rubber, sulphur cross links are introduced. Natural rubber is mixed with 3 to 5% sulphur and heated at $100-{150}^{o}C$ to form cross linking of cis-1,4 polyisoprene chains through disulphide bonds (-S-S-) . Vulcanization of rubber makes it more strong, tough and elastic.