Initiators of cationic polymerization of olefins arising from interaction between two lewis acids

Abstract

Abstract By an interaction between two relatively weak Lewis acids, highly effective initiators of the cationic polymerization of olefins are obtained. Under conditions where the polymerization of isobutylene with BCl 3 , TiCl 4 or VOCl 3 does not proceed in methylene chloride or heptane solution, it can be initiated with a small or even trace quantity of FeCl 3 . The formation of complex compounds was investigated by UV spectroscopy and by the conductometric titration in methylene chloride. Hydrogen chloride, which has no co‐initiation effect on polymerization in heptane solution initiated with metal halides alone, is an effective co‐initiator in a mixture of Lewis acids containing a small quantity of FeCl 3 . The results support a hypothesis regarding the initiation of polymerization of olefins by cations of metal halides arising by the ionization of a weaker acid with a stronger one.