Unoriented polypropylene molding
US6258893A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 15, 1999 |
| Grant date | Jul 10, 2001 |
| Priority date | — |
| Expiry date | Nov 15, 2019 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08L23/16
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
An unoriented polypropylene-based film or sheet possessing excellent impact resistance at low temperature, transparency, heat resistance at low temperature and excellent tear strength and/or stress whitening resistance. A molding material which comprises a polypropylene-based resin material comprising 40 to 80% by weight of crystalline polypropylene and 60 to 20% by weight of propylene-.alpha.-olefin copolymer containing 20 to 80% by weight of propylene polymerization units, the propylene-.alpha.-olefin copolymer dispersed as particles in the crystalline polypropylene, is unoriently molded to afford a film-shaped or sheet-shaped molding, wherein the particle diameter have an aspect ratio (L/D) of mean dispersed particle length (L) to mean dispersed particle diameter along the thickness of the molding (D) of 30 or more in a cross section of the molding along the MD direction, and the mean dispersed particle diameter of 0.3 .mu.m or less.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.