Propylene-ethylene random block copolymer and biaxially oriented multi-layer film using the same as a surface layer
US7390575B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 18, 2004 |
| Grant date | Jun 24, 2008 |
| Priority date | — |
| Expiry date | Feb 2, 2026 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31938
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A polyolefin based biaxially oriented multi-layer film having at least one surface layer comprise of the propylene-ethylene random block copolymer;The propylene-ethylene random block copolymer obtained through sequential polymerization catalyzed by a metallocene component which is composed of 30 to 70 wt % of a propylene-ethylene random copolymer component having an ethylene content of 1 to 7 wt % produced in the first step of the polymerization and from 70 to 30 wt % of a low crystallinity or an amorphous propylene-ethylene random copolymer component produced in the second step of the polymerization having an ethylene content of 6 to 15 wt % higher than that of the polymer component obtained in the first step, wherein that shows a single peak at 0° C. or lower in the temperature-loss tangent (tan δ) curve obtained by dynamic mechanical analysis (DMA).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.