Patent · US Expired

Method of polymerizing olefins using unsupported catalyst compositions

US6426394B1 · kind B1 · utility

4Cited by
2References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 10, 1999
Grant dateJul 30, 2002
Priority date
Expiry dateDec 10, 2019

Classification

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

Abstract

Methods of polymerizing olefins in the gas phase using unsupported catalyst compositions are disclosed. At least one olefin monomer is polymerized in a gas phase reactor in the presence of an unsupported liquid catalyst composition whereby the method reduces reactor fouling by maintaining the partial pressure of the primary olefin monomer that is polymerized below about 240 psi. in the reactor. The invention is particularly useful for, but is not limited to polymerizing propylene or copolymerizing propylene with olefins having two or more carbon atoms. The method described herein produces a polymer product having controlled, uniform particle size, narrow molecular weight distribution, high bulk density and stereoregularity, and prevents and/or inhibits reactor fouling during catalyst delivery and during polymerization.

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