MANUFACTURING METHOD OF POLYIMIDE COMPOSITE MEMBRANE FOR SEPARATING WATER/ORGANIC SOLVENT

摘要

PURPOSE: A preparation method of polyimide composite membrane by interfacial-polymerizing diamine aqueous solution and diacylchloride-diester and followed by heat curing is provided which has good permeability and preferential segregation properties for separating water from water/organic solvent mixtures selectively. CONSTITUTION: A diamine aqueous solution(H2N-R-NH2) and diacylchloride-diester organic phase of formula(2) are interfacial-polymerized on a porous holder to give a polyamic ester membrane, which is cured at 100-300°C to give a polyimide composite membrane having a conversion rate to polyimide of 30-80%. In formula(2), R is -(CH2)m- or phenyl, m is 0-10. The concentration of the diamine aqueous solution(H2N-R-NH2) is 0.2-10 mol/L. The process is useful for separating water from water/organic solvent mixtures selectively by a permeability evaporation or a reverse osmosis.