Patent ID: 6872682
Filing Date: 2005-03-29
Classification: C08F

Abstract:
1. A catalyst system for the polymerization of α-olefins, the catalyst being prepared by a process including a catalyst activation comprising the contacting of a solid transition metal compound with an organoaluminum compound, and a catalyst prepolymerization comprising the polymerization of a premonomer in the presence of the activated catalyst, the catalyst activation comprising a first step of contacting the solid transition metal compound with a first organoaluminum compound in the presence of an oil to give a first reaction mixture wherein the weight ratio between said solid transition metal compound and said oil is between 0.1 and 5, and a second step of contacting the first reaction mixture with a second organoaluminum compound to give a second reaction mixture, the second organoaluminium compound being the same as or different from the first organoaluminum compound.