Catalysts for the polyerization of olefins.

摘要

A catalyst for the polymerization of olefins, containing magnesium, chlorine, aluminium and at least one transition metal, in a dispersed or emulsified form within an inert diluent, is obtained by: contacting, in an inert diluent, a magnesium dialkyl and aluminium trichloride, in a molar ratio equal or almost equal to 2/1, at a temperature lower than 105 DEG C to obtain a catalyst precursor in a suspended form, or at a temperature higher than 105 DEG C to form a catalyst precursor in the form of a colloidal emulsion, in the diluent used; and contacting said suspended or emulsified precursor with at least one compound of a transition metal to form a catalyst in the form of a suspension or emulsion respectively. f