Question

Which one of the following statements is not true?

• A. Buna-S is a copolymer of butadiene and styrene
• B. Natural rubber is a 1, 4-polymer of isoprene
• C. In vulcanization, the formation of sulphur bridges between different chains make rubber harder and stronger
• D. Natural rubber has the trans configuration at every double bond

Answer 1

Answer: (D)

Natural rubber is cis-1,3 polyisoprene and has only cis configuration about the double bond as shown below

whereas in Gutta-percha, only trans configuration exists about the double bond. Buna-S is a copolymer of butadiene and styrene.