Patent · US Expired

Propylene polymer resin with improved properties

US7220812B2 · kind B2 · utility

4Cited by
1References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 27, 2005
Grant dateMay 22, 2007
Priority date
Expiry dateJul 27, 2025

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/31855
  • WIPO fieldMacromolecular chemistry, polymers
  • WIPO sectorChemistry

Abstract

The present invention relates to a process for the production of a propylene polymer in a multistage polymerisation process comprising the polymerisation of propylene in the presence of a catalyst in a first reaction zone comprising at least one slurry reactor to give a first polymerisation product, transferring said first product to a second reaction zone comprising at least one gas phase reactor and continuing polymerisation of propylene in the gas phase in the presence of said first polymerisation product which is characterised in that the temperature in both the slurry and the gas phase reactor is at least 75° C. and the product of at least one reactor is having an ethylene content in the range of 0.05 to 0.5 wt. %. Furthermore, the invention relates to a propylene polymer obtainable by the inventive process, to a propylene polymer which is characterised in that it comprises ethylene comonomer in an amount of 0.05 to 0.5 wt. %, is having a xylene solubles contents of 3.0 wt. % or less and is having a maximum in its temperature rising elution fractionation (TREF)-function at 120° C. or less, and to articles such as fibres, non-wovens, films and sheets comprising the inventive po…

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