Homogeneous olefin polymerization catalyst by abstraction with lewis acids
US5721185A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 5, 1992 |
| Grant date | Feb 24, 1998 |
| Priority date | — |
| Expiry date | May 5, 2012 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08F2420/02
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A process for preparing addition polymerization catalysts having a limiting charge separated structure corresponding to the formula: EQU LMX.sup.+ XA.sup.-, wherein: PA1 L is a derivative of a substituted delocalized .pi.-bonded group imparting a constrained geometry to the metal active site and containing up to 50 nonhydrogen atoms; PA1 M is a metal of Group 4 or the Lanthanide series of the Periodic Table of the Elements; PA1 X independently each occurrence is hydride or a hydrocarbyl, silyl or germyl group having up to 20 carbon, silicon or germanium atoms; and PA1 A.sup.- is an anion of a Lewis acid, A, having relative Lewis acidity greater than or equal to that of phenylbis(perfluorophenyl)borane, said anion being compatible with the metal cation, the steps of the process comprising contacting a derivative of a Group 4 or Lanthanide metal corresponding to the formula: EQU i LMX.sub.2, wherein PA1 L, M, and X are as previously defined, with the Lewis acid, A, under conditions to cause abstraction of X and formation of the anion XA.sup.-.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.