Patent · US Expired

Production of polyethylene having improved crack and/or impact resistance

US6252017A · kind A · utility

10Cited by
1References
26Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 26, 1998
Grant dateJun 26, 2001
Priority date
Expiry dateSep 26, 2018

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S526/943
  • WIPO fieldMacromolecular chemistry, polymers
  • WIPO sectorChemistry

Abstract

A process for producing polyethylene having improved crack resistance, the process comprising copolymerizing ethylene and an alpha-olefinic comonomer comprising from 3 to 8 carbon atoms, in the presence of a chromium-based catalyst in a first reactor, feeding the polyethylene copolymer thereby produced and the chromium-based catalyst to a second reactor, and in the second reactor copolymerizing ethylene and an alpha-olefinic comonomer comprising from 3 to 8 carbon atoms, in the presence of the chromium-based catalyst thereby to produce a second polyethylene product, the first and second polyethylene products forming a combined polyethylene having a monomodal molecular weight distribution.

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