| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a dope which uses a mixed solvent, has high solubility, allows slurrying and is good in uniform solubility with acrylonitrile-based copolymers, excellent in spinning stability and suitable for production of a precursor fiber for carbon fiber.SOLUTION: A dope is prepared by dissolving an acrylonitrile-based copolymer in a mixed solvent of a mass ratio of dimethylformamide/dimethylsulfoxide of 80/20 to 50/50. A method of producing a dope for a precursor, or a precursor fiber for carbon fiber, includes a step 1) of mixing dimethylformamide with dimethylsulfoxide in a mass ratio of 80/20 to 50/50 and cooling the resultant solvent to 0 to -20°C and a step 2) of mixing 18-34 pts. mass of an acrylonitrile-based copolymer with 100 pts. mass of the solvent to form a slurry and a step 3) of heating the slurry to dissolve the acrylonitrile-based copolymer.</p> |
