Surface-segregatable, melt-extrudable thermoplastic composition
US4923914A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 14, 1988 |
| Grant date | May 8, 1990 |
| Priority date | — |
| Expiry date | Apr 14, 2008 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G77/26
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A surface-segregatable, melt-extrudable thermoplastic composition suitable for processing by melt extrusion to form a fiber or film having a differential, increasing concentration of an additive from the center of the fiber or film to the surface thereof, which differential, increasing concentration imparts to the surface of the fiber or film at least one desired characteristic which otherwise would not be present, which composition includes at least one thermoplastic polymer and at least one defined additive. During formation of the fiber or film, the additive rapidly segregates in a controllable manner toward the newly-formed surface of the fiber or film, thereby resulting in a controllable differential concentration of the polymeric material, which concentration increases with increasing distance from the center of the fiber or film to its surface. The weight ratio of the polymer to the additive is in the range of from about 1 to about 1,000. The preferred polymer is a polyolefin such as polyethylene and polypropylene. The thermoplastic composition is useful in the preparation of fibers or films which have at least one surface characteristic which is different from that of the p…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.