Phillips catalyst and use thereof for the manufacture of ethylene polymers and copolymers

摘要

A novel Phillips catalyst for the homopolymerisation of ethylene and the copolymerisation of ethylene with alpha -olefins, contains, as catalytically effective components, a finely divided, phosphorus-containing chromium catalyst on an aluminum silicate support, and organolithium, organosodium, organopotassium, organomagnesium, organozinc, organoboron and organoaluminium compounds as cocatalysts. The finely divided, phosphorus-containing chromium catalyst on an aluminium silicate support can be prepared by applying at least one organic phosphorus (III), (IV) and/or (V) compound and at least one chromium (III) compound which does not react with said phosphorus compounds under the reaction conditions used, in any desired sequence, one after the other or simultaneously, to a finely divided aluminium silicate hydrogel or xerogel with formation of a catalyst precursor (A'), and activating the catalyst precursor (A') at elevated temperature in an oxidising atmosphere, forming the chromium catalyst (A). The novel Phillips catalyst gives ethylene homopolymers and copolymers of high toughness, but nevertheless good processing properties.