AN OLEFIN POLYMERIZATION OR COPOLYMERIZATION CATALYST

摘要

An olefin polymerization or copolymerization catalyst comprising particles. The particles comprise silica, a transition metal and aluminum. The silica is amorphous, porous, has a pore volume of 0.1 to 5 cm3/g and has a concentration of silanol groups which is at least 0.7 mmole per gram of silica. The transition metal and the aluminum are provided by a mixture of a metallocene and an alumoxane. The total volume of the metallocene and said alumoxane is less than or equal to the total pore volume of the silica.