Abstract: Catalytic component for the polymerization of ethylene with propylene prepared by: a) impregnation of an inert support with a solution of a compound of Vanadium having an oxidation state of between 3 and 5; b) subsequent treatment with a solution of a compound having general formula (I) RnAlXm wherein R is a C1-C20 alkyl radical, X is a halogen, n+m=3, and m is an integer between 0 and 2, the molar ratio between Aluminium in step (b) and Vanadium in step (a) being from 1/1 to 6/1.

Abstract: Solid component of a catalyst for the synthesis of elastomeric Ethylene-Propylene copolymers typically amorphous, basically consisting of a Titanium compound supported on a solid component mainly consisting of MgCl.sub.2, prepared by a process which comprises putting a solution (I), basically consisting of an organometallic compound of Aluminium diluted with aliphatic hydrocarbons, in contact with a solution (II) containingan anhydrous Magnesium halide in a composition of solvents selected from halohydrocarbons and aromatic hydrocarbons and relative mixtures, in the presence of an Aluminium trihalide;a tetravalent Titanium compound having general formula Ti(OR).sub.4-n X.sub.n.