Polyethylene film having improved barrier properties and methods of making same
US7951881B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 27, 2009 |
| Grant date | May 31, 2011 |
| Priority date | — |
| Expiry date | Apr 19, 2029 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08F110/02
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A method comprising (a) providing a catalyst comprising chromium and a support having a pore volume of from about 1.7 ml/g to about 3.5 ml/g and a surface area of from about 450 m2/g to about 700 m2/g, (b) oxidizing the catalyst to form an oxidized catalyst, (c) reducing the oxidized catalyst to form an oxidized reduced catalyst, (d) oxidizing the oxidized reduced catalyst to form an activated catalyst, (e) contacting the activated catalyst with an olefin under conditions suitable to form a polyolefin, and (f) recovering the polyolefin, wherein the polyolefin has a density of greater than about 0.960 g/cc and a melt index of from about 1.3 g/10 min. to about 2.8 g/10 min.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.