Living Polymerization of Ethylene Using Pd(II) α-Diimine Catalysts

Living polymerizations of alpha -olefins have been achieved using several catalysts based on the early transition metals. We have shown that certain late metal-based nickel aryl alpha -diimine systems polymerize alpha - olefins in a living fashion and that di- and triblock poly( alpha -olefins) can be prepared. To date, none of these systems have been shown to catalyze living ethylene polymerization. In this communication, we report conditions under which the palladium diimine catalysts can be used to carry out living ethylene polymerization to yield amorphous polyethylene with controlled molecular weights and exceptionally narrow molecular weight distributions.