| 摘要 |
PURPOSE:To obtain the title dry separation membrane having the water permeability approximate to that when moistened with a method easy to put to practical use by dipping a wet separation membrane made of polyimide resin, etc., in hot water, etc. at >=80 deg.C, and then drying the membrane. CONSTITUTION:This process is based on the fact that the water permeability and fractional mol.wt., etc., of a separation membrane made of polyimide resin or polysulfone resin or polyether sulfone resin are changed by the water at >=80 deg.C. Namely, the wet separation membrane made of the above-mentioned resin is dipped in the hot water at >=80 deg.C or pressurized hot water or steam, and then dried to obtain the dry separation membrane having water permeability approximate to that when moistened. The time to dip the membrane in hot water or pressurized water or steam is controlled from 10min-100hr, although the time depends on the dipping temp. |
