Phillips catalyst and its use for the preparation of ethylene/alpha-olefin copolymers
US5480852A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 23, 1994 |
| Grant date | Jan 2, 1996 |
| Priority date | — |
| Expiry date | May 23, 2014 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08F10/00
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A novel Phillips catalyst for the copolymerization of ethylene with .alpha.-olefins, contains, as a catalytically active component, a finely divided, aluminum silicate-supported, phosphorus-containing chromium catalyst. This 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 succcession in any order or simultaneously, to a finely divided aluminum silicate hydrogel or xerogel with formation of a catalyst intermediate and activating the catalyst intermediate at elevated temperatures in an oxidizing atmosphere, with the result that the chromium catalyst is formed. The novel Phillips catalyst gives ethylene/.alpha.-olefin copolymers in which the comonomers are more uniformly distributed over the copolymer chains than is the case with ethylene/.alpha.-olefin copolymers which have been prepared with the aid of conventional Phillips catalysts. Moldings which have been produced from the ethylene/.alpha.-olefin copolymers obtained in the novel procedure have a particularly high environmental stress cracking resistance and …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.