Process for preparing polyolefins

摘要

Polyolefins exhibiting better particle properties are prepared by polymerizing an olefin or olefins in the presence of a catalyst comprising a solid catalyst component and an organometallic compound, the solid catalyst component being prepared by reacting the following components [I] and [II] at first and then reacting the reaction product thus obtained with the following component [III]: [I] a reaction product obtained by reacting: (1) a silicon oxide and/or an aluminum oxide, and (2) a titanium compound, or a titanium compound and a vanadium compound, [II] a reaction product obtained by the reaction of: (1) a magnesium halide, (2) a compound represented by the general formula Me(OR)nXz-n wherein Me represents an element of J Groups I to IV in the Periodic Table, z represents the valence of the element Me, n is 0