| 摘要 |
PURPOSE:To obtain the title fiber suitable for battery separator by dissolving a mixed polymer comprising PVC, polymethyl methacrylate and polysulfone in a specific ratio in a solvent such as DMF to give spinning dope, extruding the dope in a coagulating bath, drawing and relaxing the fiber by wet heat. CONSTITUTION:A mixed polymer comprising 20-40wt.% PVC having 800-2,500 polymerization degree, 20-65wt.% polymethyl methacrylate and 15-40wt.% polysulfone is dissolved or dispersed in a solvent selected from dimehtylacetamide, DMF, dimethyl sulfoxide and acetone to give spinning dope, which is extruded into a coagulating bath containing 20-60wt.% coagulant, comprising the coagulant and the same solvent used in the spinning dope, drawn at >=2.5 draw ratio by wet heat, subjected to 7-15% wet heat relaxation in a boiling water to give the aimed fiber having >=1.5% weight loss of fiber after one hour treatment in 30% aqueous solution of KOH under normal-pressure boiling state, <=15% shrinkage percentage in boiling water and >=1.0g/d filament strength. |
