Patent · US Expired

Mixed chromium catalysts and polymerizations utilizing same

US5198400A · kind A · utility

22Cited by
9References
30Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 26, 1991
Grant dateMar 30, 1993
Priority date
Expiry dateMar 26, 2011

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC08F2410/04
  • WIPO fieldMacromolecular chemistry, polymers
  • WIPO sectorChemistry

Abstract

Mixed catalyst compositions comprised of a first supported chromium-containing catalyst component and a second supported chromium-containing catalyst component and which additionally have one or more metallic or non-metallic catalytic agents associated therewith are provided. The additional metallic or non-metallic elements associated with the catalyst components can be aluminum, titanium, zirconium, boron, phosphorous or combinations thereof. The pore volume of the silica supports used for the first and second catalyst components differs by at least 0.3 cc/g. The mixed catalyst compositions of the invention are useful for the preparation of polyolefins. They are particularly useful of polymerization of ethylene in particle form polymerizations to produce high density polyethylene blow molding resins having good processability and physical properties. The improved particle form polymerization process and products obtained thereby using the above-described mixed catalyst compositions are also described.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.