INTERFACIALLY POLYMERIZED BIPIPERIDINE-POLYAMIDE MEMBRANE FOR REVERSE OSMOSIS AND/OR NANO-FILTRATION AND PRODUCTION THEREOF

PROBLEM TO BE SOLVED: To inexpensively produce a selective water permeable membrane having excellent desalting characteristics and the resistance against a disinfecting agent such as chlorine or the like by performing the interfacial polymn. of a monomeric bipiperidine reactant and a specific monomeric amine- reactive polyfunctional aromatic acyl halide or the like on a microprous support. SOLUTION: In producing a water permeable membrane useful for separating a liquid mixture by reverse osmosis or nano-filtration, a monomeric bipiperidine reactant represented by the formula and a monomeric amine-reactive reactant containing polyfunctional aromatic or alicyclic acyl halide (cycloaliphatic acyl halide) or a mixture thereof are subjected to interfacial polymn. on a microporous support. In the formula, a and b are each independently an integer of 0-4, R1 and R2 are independently a nonreactive substituent. The amine-reactive reactive has at least about two acyl halide groups per a reactant molecule on an average.