Polymerization process
US7022797B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 20, 2004 |
| Grant date | Apr 4, 2006 |
| Priority date | — |
| Expiry date | Feb 20, 2024 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08F110/06
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A monomer stream containing propylene is supplied to a polymerization reactor which is operated under temperature and pressure conditions effective for the production of a stereoregular propylene polymer fluff. A titanium-based supported Ziegler-Natta catalyst having a titanium content of at least 1.7 wt. % and incorporating an internal electron donor is incorporated into the monomer stream. A trialkylaluminum co-catalyst is supplied to the monomer stream in an amount to provide an aluminum/titanium molar ratio within the range of 50–500. A silicon-based external electron donor is also supplied to the monomer stream in an amount to provide an aluminum/silicon molar ratio within the range of 10–500. Polymer fluff recovered from the polymerization reactor has a melt flow rate of at least 200 grams/10 minutes, and a xylene soluble content of no more than 4 wt. %.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.