Claims
- 1. A one-step process for producing melt spun thermoplastic polymer filaments of high orientation and tenacity, comprising extruding molten fiber-forming thermoplastic polymer in the form of filaments, while directing the thus extruded filaments into a liquid bath, while maintaining the liquid bath at a temperature at least 30.degree. C. above the glass transition temperature of the thermoplastic polymer to provide isothermal crystallization conditions for the filaments in the bath, and while withdrawing the filaments from the bath at a speed of 3000 meters per minute or greater to stress the filaments as they pass through the bath.
- 2. A process as set forth in claim 1 wherein the filaments are withdrawn at a speed which imparts a take-up stress of 0.6 to 6 g/d in the filaments.
- 3. A process as set forth in claim 1 wherein said step of directing the filaments into the liquid bath comprises directing the filaments into the liquid bath while they are still at a temperature at least 30.degree. C. above the glass transition temperature of the polymer.
- 4. A process as set forth in claim 1 wherein the fiber forming polymer is nylon and said maintaining step comprises maintaining the bath at a temperature of at least 80.degree. C.
- 5. A process as set forth in claim 4 wherein the bath is maintained at a temperature of about 90.degree. C.
- 6. A process as set forth in claim 1 including the step of controlling the conditions of the liquid bath and the speed of withdrawing the filaments from the bath so as to achieve a crystalline X-ray diffraction pattern in the filaments.
- 7. A process as set forth in claim 6 wherein said step of withdrawing the filaments from the bath comprises withdrawing the filaments from the bath at a speed of 3000 to 7000 m/min to exert a take-up stress on the filaments as they pass through the bath.
- 8. A process for producing melt spun thermoplastic polymer filaments of high orientation and tenacity, comprising extruding molten fiber-forming thermoplastic polymer in the form of filaments, directing the filaments into a liquid isothermal bath while the filaments are at a temperature at least 30.degree. C. above the glass transition temperature of the polymer, maintaining the liquid isothermal bath at a temperature at least 30.degree. C. above the glass transition temperature of the polymer, stressing the filaments as they pass through the bath to achieve a high rate of orientation and crystallization in the filaments, withdrawing the filaments from the bath, and winding the filaments on a take-up.
- 9. A process for producing melt spun thermoplastic polymer filaments of high orientation and tenacity, comprising extruding molten nylon polymer through spinneret holes to form filaments, directing the molten filaments into a liquid bath, maintaining the liquid bath at a temperature at least 30.degree. C. above the glass transition temperature of the nylon polymer to provide isothermal crystallization conditions for the filaments in the bath, and withdrawing the filaments from the bath at a speed of 3000 to 7000 m/min to exert a take-up stress on the filaments as they pass through the bath.
- 10. A process as set forth in claim 9 wherein the filaments are withdrawn at a speed which imparts a take-up stress of 0.6 to 6 g/d in the filaments.
CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation-in-part of copending application Ser. No. 07/525,874, filed May 18, 1990, now U.S. Pat. No. 5,149,480 granted Sep. 22, 1992.
US Referenced Citations (5)
Foreign Referenced Citations (1)
Number |
Date |
Country |
670932 |
Sep 1963 |
CAX |
Non-Patent Literature Citations (1)
Entry |
T. Kawaguchi, Industrial Aspects of High-Speed Spinning, Chapter 3, "Industrial View on High-Speed Spinning", pp. 8-15 (1985). |
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
525874 |
May 1990 |
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