ETHYLENE POLYMERIZATION CATALYST

摘要

An olefin polymerization catalyst system comprising (I) a polymerization catalyst produced by treating an inert support material, preferably a hydrated high surface area silica support having 1.00 to 1.50 hydroxyls per gram of silica with the reaction product of an organomagnesium compound and first a zirconium compound and/or a hafnium compound then a halogenator and tetravalent titanium compound, (II) an organoaluminum compound cocatalyst and (III) a chlorinated hydrocarbon promoter which produces polymers having broad molecular weight distribution in high yields.