Patent · US Expired

Two step process for polymerizing ethylene

US4357448A · kind A · utility

27Cited by
0References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 20, 1980
Grant dateNov 2, 1982
Priority date
Expiry dateMay 20, 2000

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S526/905
  • WIPO fieldMacromolecular chemistry, polymers
  • WIPO sectorChemistry

Abstract

Ethylene or a mixture of ethylene and a small amount of another .alpha.-olefin or diene is polymerized in two successive steps under different hydrogen partial pressures by polymerizing 30 to 70 wt. % of the ethylene or ethylene mixture to be polymerized in the presence of hydrogen at a molar ratio of ethylene or ethylene mixture to hydrogen of 1:1-8 in the first step and polymerizing the residual ethylene or the ethylene mixture at a molar ratio of ethylene to hydrogen of 1:0-0.3 in the second step, in the presence of the specific catalyst system comprising an organoaluminum compound (C) and a specific solid catalytic component (B) obtained by reacting a titanium or vanadium halogen-containing compound with a reaction product (A) obtained by reacting a Grignard reagent with a hydropoly-siloxane having the formula ##EQU1## (R.sup.1 represents an alkyl, aryl, aralkyl, alkoxy, or aryloxy group as a monovalent organic group; a is 0,1 or 2; b is 1, 2 or 3; and a+b.ltoreq.3) or a silicon compound containing an organic group and hydroxyl group in the presence or absence of an aluminum-alkoxide, aluminum alkoxy-halide halide or a reaction product obtained by reacting the aluminum compound…

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