Olefin polymerization process with novel supported titanium catalyst compositions

摘要

An olefin polymerization process comprises contacting the monomer to be polymerized with a catalyst composition comprising: an organoaluminum compound, a first electron donor, and a product obtained by contacting a solid component comprising a magnesium halide in which the atomic ratio of chlorine to magnesium is at least 1.2, a titanium halide and a second electron donor, with a halohydrocarbon and thereafter with a tetravalent titanium compound.