PURPOSE: To obtain the subject fiber having high strength and high elastic modulus in a low cost by spinning aromatic polyester formable of anisotropic melt from nozzle at a temperature higher than polymer flow temperature and specific shear rate and heat-treating at a temperature below flow temperature of resultant fiber.
CONSTITUTION: An aromatic polyester formable of anisotropic melt is subjected to spinning by extruded from nozzle at a temperature more 10°C higher than flow temperature of the polymer and ≥103 sec-1 shear rate, then the spun fiber is heat-treated at a temperature below flow temperature of the fiber for a time not increasing ≥50% of strength of the fiber in inert atmosphere, thus further heat-treated for a time increasing ≥50% of strength of the fiber in active atmosphere to afford the aimed fiber. Besides, aromatic polyester formable anisotropic melt containing ≥90wt.% repeating unit expressed by formula I and formula II, and 5-50mol% unit expressed by formula II is preferably used.
KISHINO YOSHIO
YAMAMOTO YOICHI
| JPS61138717A | 1986-06-26 | |||
| JPS63256739A | 1988-10-24 | |||
| JPS6128059A | 1986-02-07 |
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