North Carolina State University

Research, Incorporated

John A Cuculo

Ferdinand Lundberg

Paul A Tucker

Gao-Yuan Chen

Michael H Theil

Yue S Chen

Kap S Yang

Peng Chen

Richard Kotek

Gang Wu

Kazuyuki Hattori

Jeffrey Denton

Chon-Yie Lin

Jiunn-Yow Chen

Mehdi Afshari

Chon-yie Lin

Samuel M Hudson

A melt-spun highly oriented and crystalline thermoplastic filament or fiber having a tenacity of at least about 10 g/d, an elongation less than about 15-%, and a modulus of at least about 130 g/d. A method of making highly oriented and crystalline thermoplastic filaments has been developed that comprises extruding a thermoplastic polymer to form at least one molten filament. The at least one molten filament is introduced into a horizontal liquid isothermal bath. The bath is maintained at a temperature between the glass transition temperature and the melting temperature of the thermoplastic polymer. The bath increases the tension along the molten filament to form at least one partially oriented and low crystalline filament. The partially oriented filament is drawn to form the highly oriented and crystalline filament.

Process of making highly oriented and crystalline thermoplastic filaments

Cellulose solvents, cellulose compositions, and methods of making and using the same. For example, a cellulose composition including cellulose dissolved in the following solvent: an amine-based composition, provided however, the amine-based composition is not ammonia; and a salt selected from the group including a thiocyanate salt, a halide salt, and a nitrate salt. Representative amine-based compositions include hydrazine, hydrazine hydrate, and ethylenediamine.

Cellulose solvent compositions and methods of making and employing same

Ultra-oriented, crystalline synthetic filaments with a combination of high tenacity, high dimensional stability, high modulus, and a high fraction of taut-tie molecular phase are produced by extruding a fiber-forming synthetic polymer melt into a liquid isothermal bath, withdrawing the filaments from the bath and then post-treating them at a very low draw ratio. The bath is preferably maintained at a temperature of at least 30.degree. C. above the glass transition temperature of the polymer to enhance the orientation and promote the formation of stable extended chains. Polymer filaments so produced are characterized in that they have ultra-high birefringence, high tenacity and modulus, a high dimensional stability, and a high fraction of taut-tie molecular phase.

Ultra-oriented crystalline filaments and method of making same

Ultra-oriented, crystalline synthetic filaments with high tenacity are produced by extrusion of a fiber-forming synthetic polymer melt into a liquid isothermal bath maintained at a temperature of at least 30.degree. C. above the glass transition temperature of the polymer, withdrawing the filaments from the bath and then winding up the filaments. Polymer filaments so produced are characterized in that the ratio of the crystalline orientation factor (f.sub.c) to the amorphous orientation factor (f.sub.a) is 1.2 or less, and are further characterized in that the percent crystallinity is less than 40. The filaments also have a fine crystal size. The crystal size is less than 40 .ANG. in the 100 and 105 planes and less than 30 .ANG. in the 010 plane.

Ultra-oriented crystalline filaments

Ultra-oriented, crystalline synthetic filaments with high tenacity are produced by extrusion of a fiber-forming synthetic polymer melt into a liquid isothermal bath maintained at a temperature of at least 30.degree. C. above the glass transition temperature of the polymer, withdrawing the filaments from the bath and then winding up the filaments. Polyethylene terephthalate filaments so produced at 3000-5000 m/min exhibit a crystalline structure and possess birefringence of 0.20-0.22, tenacity of 7-9 g/d, break elongation of 14-30% and boil-off shrinkage of 5-10%.

Melt spinning of ultra-oriented crystalline filaments

The invention provides improved thermoplastic high strength, highly oriented fibers and a process for producing the fibers by melt spinning a thermoplastic polymer to form a threadline, preferably passing the threadline through a thermal conditioning zone and then quenching the threadline. The quenched threadline is passed through a hydraulic drag bath maintained at a temperature of greater than the glass transition temperature of the polymer which substantially increases the threadline stress and results in drawing of the threadline. The threadline is withdrawn from the drag bath at a withdrawal rate of at least 3,000 meters per minute.

Process for producing high strength, high modulus thermoplastic fibers

Ultra-oriented, crystalline synthetic filaments with high tenacity are produced by extrusion of a fiber-forming synthetic polymer melt into a liquid isothermal bath maintained at a temperature of at least 30.degree. C. above the glass transition temperature of the polymer, withdrawing the filaments from the bath and then winding up the filaments. Polyethylene terephthalate filaments so produced at 3000-5000 m/min exhibit a crystalline structure and possess birefringence of 0.20-0.22, tenacity of 7-9 g/d, break elongation of 14%-30% and boil-off shrinkage of 5%-10%.

Melt spinning of ultra-oriented crystalline polyester filaments

The high speed melt spinning of synthetic polymer fibers is provided with on-line zone heating and cooling by which the strand emerging from the spinneret is initially cooled to an optimum temperature above the glass transition point of the polymer, the maintained near that temperature for a period of time to promote development of desirable fiber properties such as crystallization and crystal orientation, and then finally cooled below the solidification point for take up.

Process for high speed melt spinning

Lyotropic mesophase (liquid crystalline) solutions of cellulose are formed in an ammonia/ammonium thiocyanate solvent. The nature of the solution can be controlled to selectively produce lyotropic cellulose mesophases having either nematic or cholesteric character. High strength, high modulus fibers are produced from a lyotropic mesophase solution of cellulose essentially in the nematic phase. The films are prepared from mesophase solutions of cellulose that are mainly in the cholesteric phase.

Anisotropic cellulose articles, fibers, and films and method of

Anisotropic cellulose solutions, fibers, and films formed therefrom

A method of forming a cellulose fiber which comprises dissolving cellulose in a solvent comprising ammonia and a salt and subsequently forming a fiber.

Growing community of inventors

Raleigh, NC, United States of America

John A Cuculo