Polyethylene composition and film having retained dart impact
US11306196B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 10, 2019 |
| Grant date | Apr 19, 2022 |
| Priority date | — |
| Expiry date | Oct 15, 2039 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08L2314/06
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A polyethylene composition including a first polyethylene which is an ethylene copolymer having a weight average molecular weight of from 70,000 to 250,000 and a molecular weight distribution Mw/Mn of <2.3, a second polyethylene which is an ethylene copolymer or homopolymer having a weight average molecular weight of less than 75,000 and a molecular weight distribution Mw/Mn of <2.3, and a third polyethylene which is an ethylene copolymer or homopolymer having a weight average molecular weight of from 100,000 to 300,000 and a molecular weight distribution Mw/Mn of >2.3, where the first polyethylene has more short chain branching than the second polyethylene or the third polyethylene. The polyethylene composition has a soluble fraction in a CEF analysis of at least 15 weight percent. A film made from the polyethylene composition may have a machine direction 1% secant modulus of ≥200 MPa (at a film thickness of about 1 mil) and an oxygen transmission rate (OTR) of ≥700 cm3 per 100 inch2 per day (at a film thickness of about 1 mil). A film made from the polyethylene composition retains much of its dart impact performance on downgauging from a thickness of 1 mil to a thickness of 0.75 …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.