Catalyst for the polymerization of olefins.

摘要

A supported solid component of catalyst, for the stereospecific polymerization of propylene and other alpha -olefins, is obtained by making a non-activated silica interact in succession with: (i) a magnesium dialkyl or halide of magnesium alkyl; (ii) a halogenating agent selected from silicon, tin and antimony halides; (iii) a titanium tetrahalide: and (iv) a Lewis base. A catalyst for the stereospecific polymerization of propylene and other alpha -olefins is composed of: (A) the solid component of catalyst; (B) an aluminium trialkyl or aluminium alkyl halide; and (C) an electron donor compound, capable of forming a complex compound with component (B).