| 摘要 |
PROBLEM TO BE SOLVED: To provide a fiber consisting of a thermoplastic resin having light weight, excellent in tensile property, insulation property, heat distortion temperature, solvent resistance, and workability, and having not high production cost.SOLUTION: There are provided a fiber consisting of syndiotactic polystyrene having tensile strength of 2.0 cN.dtex or more and a manufacturing method of the fiber. There is provided the manufacturing method including a spinning process of obtaining a fiber having the absolute value of double refraction of 0.011 or less and a stretching process of stretching the unstretched fiber obtained in the spinning process with a stretch ratio of 2.6 times of more. Especially a set spinning speed when spinning by using syndiotactic polystyrene preferably satisfies the formula (1). V<Vmax=-2.5×D+653 (1), where V is the set spinning speed (m/min.) when a molten resin extruded from a nozzle is rolled up by a winder, Vmax is a stretchable maximum spinning speed (m/min.) to the set spinning speed V, D is a ratio between discharge quantity of the resin extruded from the nozzle and speed of fiber rolled up by the winder and is represented by the formula (a). D=V×ρ×πR÷M (a), where V is the set spinning speed (m/min.) when a molten resin extruded from a nozzle is rolled up by a winder,ρis density (g/cm), R is nozzle half diameter (mm), and M is single hole discharge quantity (g/min.). |
