| 摘要 |
PURPOSE:To continuously obtain a polymer solution free from virtually heat discoloration, for use as e.g., a spinning stock solution, using a small-scale unit in a shaft time, by kneading an acrylonitrile-based polymer of a specific weight-average molecular weight in an engaging type multiple screw extruder with a solvent soluble for said polymer. CONSTITUTION:An acrylonitrile-based polymer 1 with a weight-average molecular weight of 30,000 to 130,000 is fed, via a quantitative feeder 2, into the resin feed section 11 in an engaging type multiple screw extruder followed by mix dispersion while a solvent 3 is charging into a solvent feed section 12 using a quantitative pump 4, and the resultant dispersion is heated in the earlier stage 14 of the kneading section. Thence, the resultant blend advanced in dissolution proceeds with dissolution quickly in the middle stage 15 kept at high temperatures while homogeneously kneading through shear force. The solution in which dissolution has nearly ended is then prepared, while further lowering temperature, via the later stage 16, into a homogeneous solution through shear and kneading followed by cooling to a required temperature at an extruding section 17 and then extruding the solution, thus obtaining the objective polymer solution. |
