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When isobutylene [CH2C(CH3)2] is treated with BF3, polyisobutylene is formed. Provide a step-by-step mechanism for this polymerization reaction.

User Carl Sagan
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Final answer:

The question asks about the mechanism of polymerization of isobutylene with BF3 to form polyisobutylene.

Step-by-step explanation:

The question involves the polymerization of isobutylene (CH2C(CH3)2) with BF3 to form polyisobutylene. A mechanism can be formulated based on general free radical polymerization steps: initiation, propagation, and termination. Unfortunately, the question doesn't provide sufficient information to create a detailed step-by-step mechanism for this specific reaction using BF3, which acts as a Lewis acid catalyst in cationic polymerizations, rather than a free radical initiator.

In general terms for a free radical polymerization mechanism:

  1. Initiation: A radical initiator like benzoyl peroxide breaks down to form radicals upon heating.
  2. Propagation: These radicals react with the double bond of the monomer, leading to the formation of new radicals which further react with other monomer molecules.
  3. Termination: The growing polymer chain ends when two radicals recombine, or a radical reacts with an inhibitor.

However, for the cationic polymerization of isobutylene with BF3, the steps would involve the activation of the monomer through complexation with BF3, followed by a chain growth mechanism typically involving carbocations as intermediate species, not radicals.

User SkelDave
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