Copolymerization process for the preparation of crystalline copolymers of olefins and cyclic olefins
US5621054A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 7, 1995 |
| Grant date | Apr 15, 1997 |
| Priority date | — |
| Expiry date | Jun 7, 2015 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08F4/6592
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A copolymerization process suitable for the preparation of high crystalline melting point cyclic olefin copolymers comprising contacting ethylene, and at least one cyclic olefin with an active polymerization catalyst comprising a Group 4 transition metal compound containing an asymmetrically substituted monocyclopentadienyl ancillary ligand, a bulky substituent-containing heteroatom ligand, the monocyclopentadienyl and heteroatom ligands being covalently bridged is disclosed. Ethylene/norbornene copolymers prepared in accordance with the invention exhibited crystalline melting points of about 250.degree. C., and were prepared at high catalyst activity levels with feed ratios less than 6:1 of norbornene to ethylene.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.