Ethylene/alpha-olefin copolymer
US5955639A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 29, 1993 |
| Grant date | Sep 21, 1999 |
| Priority date | — |
| Expiry date | Jul 29, 2013 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P20/52
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
A copolymer of ethylene and an alpha-olefin having an ethylene content of from 30 to 90 mole %, a number average molecular weight of from 300 to 30,000 and a molecular weight distribution defined by a Q value (the ratio of the weight average molecular weight to the number average molecular weight) of not more than 3 and a Z value (the ratio of the maximum value of the molecular weight to the minimum value of the molecular weight when the molecular weight is measured by gel permeation chromatography) of from 15 to 200. The said copolymer can be produced by a process comprising copolymerizing ethylene with an alpha-olefin in the liquid phase in the presence of a polymerization catalyst composed of a combination of a soluble vanadium compound and an organoaluminum compound in the co-presence of hydrogen, characterized in that PA1 (a) the copolymerization is carried out in a continuous manner, PA1 (b) the concentration of the vanadium compound in the polymerization system is maintained at 0.3 to 30 millimoles/liter, and PA1 (c) the vanadium compound is supplied to the polymerization system as a solution in a polymerization medium in a concentration which is 1 to 5 times the concentrati…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.