PURPOSE: To provide a semipermeable membrane which contains a sulfonated aromatic polyether ketone and a completely aromatic polyamide as the main constituents, is excellent in hydrophilicity, can absorb a large quantity of water, and has resistance to hydrolyzing agents, heat and solvents, low protein adsorbency and good wettability.
CONSTITUTION: A semipermeable membrane of a homogenous polymer alloy containing a sulfonated aromatic polyether ketone and a completely aromatic polyamide as the main constituents. This polymer alloy may contain in addition poly-N-vinyl-2-pyrrolidone or its copolymer with vinyl acetate. The alloy preferably comprises one that does not contain a partially aliphatic polyamide, and it contains a sulfonated aromatic polyether ketone of the formula (wherein -Ar- is p- or m-phenylene; -Ar'- is naphthylene or the like; X, M and N are each 0 or 1; Y is 0 to 3; p is 1 to 4; and 20-100% of the O-phenylene-O units are substituted by SO3H).
FUREDEI HERUMAA METSUTSUMAN
OTSUTOO HERUMANNSHIEENHEAA
