PROCESS FOR THE PREPARATION OF A SUPPORTED CATALYST BASED ON VANADIUM COMPOUNDS FOR THE POLYMERISATION AND COPOLYMERISATION OF ETHYLENE AND THE CATALYSTS OBTAINED THEREBY

摘要

New catalysts which can be used for the polymerization and copolymerization of ethylene, comprising a support consisting basically of magnesium chloride on which is deposited by precipitation a vanadium compound, obtained by bringing a vanadium compound in which the vanadium is at one of the two maximum valencies 4 and 5 in contact with a support consisting basically of magnesium chloride and optionally of aluminium chloride and comprising products with an Mg-C bond.