Acylating agents, polymeric types

Initiators which have been used for the cationic polymerization of 8-capro-lactone include protic acids, Lewis acids, stabilized carbocations and acylating agents. The mechanism involves the formation of charged species, followed by the ring opening of the activated lactone by the attack of another monomer and insertion into the chain. This type of polymerization is not very significant for the production of PCL. The reaction is difficult to control and transesterification reactions, which occur, limit the molecular weight of the obtained... 

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