Patent ID: 7019090
Filing Date: 2006-03-28
Classification: C08F,Y10S

Abstract:
1. A catalyst obtained by the process for the manufacture of a prepolymerized catalytic composition for the polymerization of olefins comprising: a—the manufacture of a first prepolymer by prepolymerizing at least one first olefin in the presence of a solid catalyst A, then b—the impregnation of the said first prepolymer with a solution of a catalyst B, then c—the prepolymerization of at least one second olefin in the presence of the impregnated first prepolymer to form the catalyst; wherein the solid catalyst A contains magnesium, chlorine and titanium atoms, and the prepolymerization in the presence of catalyst A is carried out in the presence of a cocatalyst; wherein the catalyst B is selected from compounds of formula ML the catalyst A and the catalyst B containing a transition metal and the catalyst A and the catalyst B being different and not being such that at the same time: the catalyst A comprises a group with a cycloalkadienyl skeleton, and the catalyst B comprises a group with a cycloalkadienyl skeleton.