| 摘要 |
PURPOSE:To wet a dry polysulfone semipermeable membrane again without deforming or deteriorating it, by treating it with an aq. alcohol soln. of a specified concn. CONSTITUTION:A polysulfone film having 0.58ml/cm<2>.min pure water permeation speed in 1kg/cm<2> pressure, and in the case of an aq. soln. of 0.2% polyethylene glycol having 20,000 average mol.wt., 69.0% exclusion rate and 0.16ml/ cm<2>.min in 4kg/cm<2> pressure is immersed in an aq. 30% glycerin soln. for 24hr, and dried at room temp. to give a dried membrane. The membrane is immersed in an aq. 40% ethanol soln. at 20 deg.C for 12hr to rewet it. The obtained rewet membrane is found to have 0.59ml/cm<2>.min pure water permeation speed, 70.3% polyethylene glycol aq. soln. exclusion rate, and 0.16ml/cm<2>.min water permeation speed, and to be able to restore the initial performance of the wet membrane. |
