| 摘要 |
PURPOSE:To obtain the titled yarn useful as a precursor for carbon fiber, by dissolving a polymer for polyacrylonitrile having specific molecular weight in a solvent with deaerating it under reduced pressure, spinning it, coagulating it, drawing and drying it under specific conditions. CONSTITUTION:A polymer consisting essentially of acrylonitrile, having >=400,000 weight-average molecular weight, is dissolved in a solvent (e.g., aqueous solution of a rhodanide, etc.) while being deaerated under reduced pressure, the prepared stock solution for spinning is spun, and coagulated by the use of a low-temperature coagulating means using preferably an inorganic solvent. The yarn is then drawn in hot water and in a high-boiling medium (e.g., polyhydric alcohol, etc.) having >=100 deg.C boiling point successively, and subjected to multi-stage drawing under conditions wherein temperature is raised as it reashes post-process. The yarn is then preferably washed, dried under tension at <=130 deg.C and tensile strength is made >=20g/d, to give the desired yarn. |
