PROCESS FOR THE PREPARATION OF A SOLID COMPONENT OF CATALYSTFOR THE (CO)POLYMERIZATION OF ETHYLENE

摘要

A process is described for the preparation of a solid component of cataly st active in the (co)polymerization of ethylene and able to give (co)polymers of ethylene having from middle to wide distribution of the molecular weight and monomodal distribution of molecular weights, in processes operating in a single step, in suspension or in gaseous phase. Said solid component of catalyst contains magnesium, chlorine, silicon, titanium and at least anothe r transition metal on a solid, granular and porous carrier and is obtained by treating the carrier, in succession, with: a compound of a metal selected fr om hafnium, zirconium or vanadium; a magnesium dialkyl or magnesium alkyl halid e; a silicon chloride; and a titanium compound.