Consider the monomeric unit `H₂C=C(CH₃)-CH=CH₂`. What is the common name of the polymer formed from this monomer, and what type of polymerization mechanism is typically employed to produce it for use in synthetic rubber?
Correct: B
The monomer H₂C=C(CH₃)-CH=CH₂ is 2-methyl-1,3-butadiene, commonly known as isoprene. The polymer formed from isoprene is polyisoprene. While natural rubber (cis-polyisoprene) is a polymer of isoprene, the question asks for the common name of the polymer formed FROM THIS MONOMER, implying a synthetic process leading to a rubber. Synthetic polyisoprene can be produced to mimic natural rubber. The options need careful evaluation. Neoprene is poly(chloroprene). Buna-N is a copolymer of 1,3-butadiene and acrylonitrile. Butyl Rubber is a copolymer of isobutylene and isoprene. Natural Rubber itself is a biopolymer with specific stereochemistry. Among the given choices, 'Polyisoprene (Natural Rubber)' is the polymer formed from isoprene. However, the question asks for the COMMON NAME OF THE POLYMER. The 'natural rubber' part implies the cis-1,4 configuration. If it's just 'polyisoprene', it's a general term. The polymerization of isoprene to form synthetic polyisoprene, particularly the cis-1,4 form that resembles natural rubber, typically utilizes Ziegler-Natta catalysts (coordination polymerization) for stereochemical control. If we strictly consider 'common name', 'Natural Rubber' is a common name for cis-polyisoprene. So, option B is the most accurate in terms of monomer and mechanism for achieving a specific, useful form of polyisoprene.