| 摘要 |
PURPOSE:To obtain a polysulfone membrane having a pore size of 0.03-0.2mum and high in water permeability, by setting a coagulation bath to a high temp. in a wet membrane forming process. CONSTITUTION:A polysulfone resin represented by formula is dissolved in a solvent capable of dissolving said polysulfone resin and substantially miscible with water at an ambient temp. As a concrete example, when a solvent mixture consisting of N-methyl-2-pyrrolidone and ethylene glycol monoethyl ether, of which the volumetric ratio is changed in a range of 100:0-43:47, is used, the pore size and water permeability of a membrane can be controlled to a certain degree without changing the other condition. The concn. of the polysulfone resin is pref. in a range of 16-22g/dl. By changing the temp. of a coagulation bath within a range of 35-95 deg.C, the membrane, of which the pore size is in a range of 0.03-0.2mum and the water permeability is 1.5m<3>/m<2>hrkg/cm<2> or more, is obtained. |
