High temperature olefin polymerization process
US5907021A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 26, 1998 |
| Grant date | May 25, 1999 |
| Priority date | — |
| Expiry date | Mar 26, 2018 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P20/582
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A polymerization process for olefinically or acetylenically unsaturated monomers is disclosed. The process comprises contacting the one or more of the monomers with a suitable ionic catalyst system in the presence of a long-chain, linear alkyl ligand-containing organo aluminum compound. Preferred ionic catalysts are derived from 1) bridged hafnium compounds, 2) silicon bridged monocyclopentadienyl titanium compounds and 3) unbridged, bulky Group 15 containing, bulky monocyclopentadienyl titanium compounds, and a non-coordinating anion precursor compound. A class of preferred anion precursors consists of hydrated salts comprising a Group 1 or 2 cation and a non-coordinating anion. Using the preferred ionic catalysts high temperature processes, e.g., at or above 90.degree. C. can be conducted to prepare polyolefins, particularly ethylene copolymers, of both high molecular weight and high comonomer content.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.