Polymerisation of vinyl monomers by transition-metal allyl compounds. Part I

Abstract

A range of transition-metal π-allyl compounds has been tested for polymerisation activity with vinyl monomers in general and with methyl methacrylate in particular. They show considerable variation in activity, and allyl-chromium and -zirconium were selected for special study. The poly(methyl methacrylates) obtained using allyl-chromium have been examined for tacticity and other evidence relating to the polymerisation mechanism. The mechanism appears to be anionic in character. The allylzirconium does not polymerise methyl methacrylate but reacts to form a new compound; the nature of this compound and those formed by allyl-chromium and -zirconium with esters and ketones have been determined.