Hoechst Celanese Corporation

Celanese Acetate Limited

Michael J Jaffe

M Ishaq Haider

Eui W Choe

Subhash Makhija

John A Flint

Edward C Chenevey

Marie Borzo

Joseph J DiBiase

John Edward Cornetta

The present invention discloses and claims a novel process for the formation of high denier as-spun and heat-treated filaments of a thermotropic liquid crystalline polymer. Preferred embodiments include process for the formation of as-spun and heat treated 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 of an aspect ratio of greater than about 1 and less than about 15 to form a filament; and (c) winding the filament at a draw-down ratio of at least about 4. The filaments so formed are of at least 50 denier per filament (dpf) and feature essentially uniform molecular orientation across the 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 retaining at least 80 to 90 percent of the properties expected of conventional low denier (5 to 10 dpf) filaments.

Process for making high denier filaments of thermotropic liquid

A method of making controlled sequence condensation copolymers from mer systems capable of forming at least two unique recurring units is disclosed and claimed. Sequenced polyesters containing the residue of hydroxyacids are specifically exemplified.

Condensation copolymers with sequenced mer structure

Growing community of inventors

Maplewood, NJ, United States of America

Michael J Jaffe