Propylene polymers incorporating polyethylene macromers
US6660809B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 6, 1998 |
| Grant date | Dec 9, 2003 |
| Priority date | — |
| Expiry date | Feb 6, 2018 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08L2314/06
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A polyolefin product is provided which comprises a branched olefin copolymer having an isotactic polypropylene backbone, polyethylene branches and, optionally, one or more comonomers. The total comonomer content of the branched olefin copolymer is from 0 to 20 mole percent. Also, the mass ratio of the isotactic polypropylene to the polyethylene ranges from 99.9:0.1 to 50:50. Additionally, a process is provided for preparing a branched olefin copolymer which comprises:a) copolymerizing ethylene, optionally with one or more copolymerizable monomers, in a polymerization reaction under conditions sufficient to form copolymer having greater than 40% chain end-group unsaturation;b) copolymerizing the product of a) with propylene and, optionally, one or more copolymerizable monomers, in a polymerization reactor under suitable polypropylene polymerization conditions using a chiral, stereorigid transition metal catalyst capable of producing isotactic polypropylene; andc) recovering a branched olefin copolymer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.