| 摘要 |
PURPOSE:To vary remarkably the fractional characteristic without damaging the strength and the water permeability of a membrane by impregnating with a liquid consisting of an aromatic compd. and having an excellent affinity for a polysulfone resin. CONSTITUTION:A polysulfone resin consisting of a polymer alone having the formulated repeating unit or of the mixture of both polymers is used. Benzene, toluene, xylene, aniline, pyridine, phenol, cresol, etc. are used as a liquid consisting of an aromatic compd. The fractional characteristic of a membrane can be optionally regulated by impregnating with said solns. The time of impregnation is suitably regulated to about one hour, and the concn. of the aromatic compd. is preferably regulated to 30-100wt%. The membrane contg. water is dehydrated by alcohol, etc., impregnated with the soln. of the aromatic compd., and again hydrated thereafter. |
