Abstract: A method of polymerizing olefins with a catalyst component which comprises 1) the reaction product of a magnesium alkoxide of the formula M(OR)2, wherein M is magnesium, O is oxygen, R is a hydrocarbyl having from 1 to 20 carbons atoms, and a halogenating agent; 2) an electron donor wherein the electron donor is diethyl phthalate or di-isobutyl phthalate; 3) a titanating agent. The catalyst component is activated with an organoaluminum cocatalyst. An external donor, specifically dicyclopentyl dimethoxysilane or cyclohexylmethyldimethoxy silane, can be added as a stereoselectivity control agent. The activated catalyst is used in the polymerization of olefins, particularly propylene, to obtain a polymer product with a broad molecular weight distribution.

Abstract: A method of forming a polyolefin catalyst component which includes chlorinating magnesium ethoxide, and then treating the product first with an electron donor, particularly diethyl phthalate or di-isobutyl phthalate, at a relatively low donor level, and then second with a titanating agent, such as titanium tetrachloride, to produce a catalyst component. The catalyst component is activated with an aluminum alkyl cocatalyst. An external electron donor, such as an organosilane compound, is added for stereoselectivity control. The activated catalyst is used in the polymerization of olefins, particularly propylene, to obtain a polymer product with a broad molecular weight distribution.

Abstract: The present invention provides a catalyst and a process for increased catalyst activity and polymer yield. The catalyst system used in the process includes at least two supported metallocene catalyst precursor in combination with an oxyorganoaluminum. The process can be applied to the polymerization of olefins, preferably olefin of three carbon atoms and higher, particularly propylene. The catalyst activity and polymer yield for a dual supported metallocene catalyst are increased over that for a single supported metallocene catalyst. The polymer produced by this dual supported metallocene system has a relatively broad molecular weight distribution.