Process for preparing polypropylene
US6437063B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 23, 2000 |
| Grant date | Aug 20, 2002 |
| Priority date | — |
| Expiry date | Jun 29, 2020 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S526/943
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
The present invention concerns a process for producing a propylene polymer nucleated with a polymeric nucleating agent containing vinyl compound units. The method comprises modifying a catalyst by polymerizing a vinyl compound in the presence of said catalyst in a medium, which does not essentially dissolve the polymerized vinyl compound, and by continuing the polymerization of the vinyl compound until the concentration of unreacted vinyl compounds is less than about 0.5 wt-%. The thus obtained modified catalyst composition is used for polymerizing propylene optionally together with comonomers to produce in the presence of said modified catalyst composition. Modification of the catalyst according to the present invention will reduce production costs and provide highly reliable catalyst activity.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.