Bimetallic catalyst, method of polymerization and bimodal polyolefins therefrom
US8557935B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 13, 2012 |
| Grant date | Oct 15, 2013 |
| Priority date | — |
| Expiry date | Jun 13, 2032 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08F110/02
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
Bimetallic catalysts, methods of producing bimetallic catalysts comprising a modified Ziegler-Natta catalyst and a metallocene, and methods of olefin polymerization using such catalysts are provided. The method of producing the bimetallic catalyst may include combining (a) a Ziegler-Natta catalyst comprising a Group 4, 5 or 6 metal halide and/or oxide, optionally including a magnesium compound, with (b) a modifier compound (“modifier”), wherein the modifier compound is a Group 13 alkyl compound, to form a modified Ziegler-Natta catalyst. The modified Ziegler-Natta catalyst is preferably non-activated, that is, it is unreactive towards olefin polymerization alone. The molar ratio of the Group 13 metal (of the modifier) to the Group 4, 5 or 6 metal halide and/or oxide may be less than 10:1. The bimetallic catalysts are useful in producing bimodal polymers, particularly bimodal polyethylene, having a Polydispersity (Mw/Mn) of from 12 to 50, which may be used in pipes and films.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.