Hydrogen atom transfer from vinyl ethers

Chain Transfer. Chain transfer is the most important chain-breaking reaction in carbocationic polymerization. It can be considered as a subcase of termination, when this latter is accompanied by reinitiation. In chain-transfer reactions the active center is transferred to a new site to imreacted monomer or initiator, the preformed polymer, or the solvent. This can happen by /3-proton elimination from the growing chain, or Friedel-Crafts alkylation of aromatic rings. /8-Hydrogen atoms of the propagating carbenium ions are quite acidic owing to the delocalization of the positive charge. In isobutylene, vinyl ether, and styrene... 

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