Triethyl oxonium fluoroborate either preformed or preparedin situ by the reaction of boron trifluoride etherate with epichlorohydrin does not initiate the homo or copolymerization of vinyl monomers. Small conversions to copolymers by use of these initiators with low methyl methacrylate incorporation is ascribed to conventional vinyl copolymerizations, initiated by free boron trifluoride and/or protonic impurities in the system.
