Process for making high denier multilobal filaments of thermotropic liquid crystalline polymers and compositions thereof
US6187437A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 10, 1998 |
| Grant date | Feb 13, 2001 |
| Priority date | — |
| Expiry date | Sep 10, 2018 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/2975
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
The present invention discloses and claims a novel process for the formation of high denier as-spun and heat-treated multilobal filaments of a thermotropic liquid crystalline polymer. Preferred embodiments include process for the formation of as-spun and heat treated octalobal monofilaments of a few wholly aromatic polyesters and polyesteramides. The process involves (a) heating of a thermotropic liquid crystalline polymer to above its melting transition temperature; (b) passing said molten polymer through an extrusion chamber equipped with an extrusion capillary having a multilobal cross-section to form a multilobal filament; and (c) winding the filament at a suitable draw-down. The filaments so formed are of at least 50 denier per filament (dpf) and feature essentially uniform molecular orientation across their cross-section. In a final optional step, the filaments are heat treated in stages to form filaments exhibiting excellent tensile properties. Both as-spun and heat-treated filaments feature remarkably good tensile properties comparable to those of round filaments. Most importantly, the multilobal filaments of this invention feature much superior adhesion properties than the…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.