Patent · US Expired

High molecular weight homopolymers and copolymers of ethene

US5756627A · kind A · utility

0Cited by

8References

3Claims

0Family size

Assignee

BASF SE

Inventors

Hans Gropper · Schifferstadt, DE
Guido Funk · Worms, DE
Erich Kolk · Bad Dürkheim, DE
Dieter Oeder · Bad Dürkheim, DE

Key dates

Filing date	Sep 30, 1992
Grant date	May 26, 1998
Priority date	—
Expiry date	Sep 30, 2012

Classification

Technology area (CPC C)Chemistry; Metallurgy
CPC primaryC08F110/02
WIPO fieldMacromolecular chemistry, polymers
WIPO sectorChemistry

Abstract

The present invention relates to high molecular weight homopolymers and copolymers of ethene, which homopolymer or copolymer is obtained by polymerizing the monomer(s) at a temperature of from 70.degree. to 150.degree. C. and under a pressure of from 2 to 150 bar in contact witha chromium trioxide catalyst, PA1 (1) loading a support based on silicon dioxide with PA1 (2) either chromium trioxide or a chromium compound capable of being converted to chromium trioxide under the conditions of stage (3) below and then PA1 (3) heating the resulting intermediate in a gas stream containing oxygen, the support (1) being a special silica xerogel obtained by extracting not more than 30% of the water from a silica hydrogel by means of an alkanol, an alkanone or a mixture thereof followed by drying, comminution and fractional screening.

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