| 摘要 |
Polyacrylonitrile (PAN) fibers are prepared by forming a 2-15 weight % solution of PAN of Mw at least 500,000, extruding, cooling to below the gel temperature, extracting and drying. At least one of the gel fiber, the fiber containing extraction solvent and the dried gel is stretched. The product PAN fibers have a Mw at least 500,000 (eg. 1,000,000-4,000,000 or 1,500,000-2,500,000), a tenacity at least 5 g/den (e.g., at least 7 g/den) and a secant modulus at least 100 g/den (e.g. at least 125 g/den). |
