KATALYSATOR OG PREPOLYMER BENYTTET FOR PREPOLYMERISASJON AV OLEFINER, OG (KO)POLYMER AV ETYLEN SOM KAN OPPNAAS DERFRA

摘要

The present invention relates to a process for the preparation of a catalyst based on zirconium, titanium and / or vanadium, supported on the spheroidal particles of magnesium chloride, for the (co -) polymerization of olefins. The preparation consists of contacting a support comprising a magnesium dichloride and an organic compound, the electron donor, d1, free of labile hydrogen, a support having a shape spheroidal, a given size and a narrow particle size distribution, with an electron donor compound, d2, containing a labile hydrogen. The product resulting solid is then placed in contact with an organic compound, zirconium, such as a zirconocene, and a titanium halide and / or vanadium, and possibly with an aluminoxane. The catalyst can be used in the (co) - polymerization of ethylene in suspension in an aliphatic hydrocarbon, or in gaseous phase in a fluidized bed. The polymers or copolymers of ethylene, have a molecular weight distribution which is relatively wide, which may be of a bimodal.