Polypropylene articles and method for preparing same
US4950549A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 20, 1989 |
| Grant date | Aug 21, 1990 |
| Priority date | — |
| Expiry date | Mar 20, 2009 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31855
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
Polypropylene articles are provided. The polypropylene articles comprise non-crystalline mesomorphous polypropylene having olefinic unsaturation-containing monomers graft-polymerized thereon by ionizing radiation in a dosage sufficient to degrade crystalline polypropylene. The irradiated polypropylene articles retain useful tensile properties after storage periods of as long as at least about four months. Further provided is a method for preparing irradiated polypropylene articles having olefinic unsaturation-containing monomers graft-polymerized thereon comprising the steps of melt extruding polypropylene; quenching the extruded polypropylene immediately after extrusion to provide non-crystalline mesomorphous polypropylene; coating the non-crystalline mesomorphous polypropylene with an ionizing radiation graft-polymerizable monomer; and irradiating the coated non-crystalline mesomorphous polypropylene with a dosage of ionizing radiation sufficient to degrade crystalline polypropylene and sufficient to effect graft-polymerization of the monomer onto the surface of the polypropylene.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.