ION-EXCHANGE MEMBRANE AND METHOD FOR PRODUCING IT

摘要

PROBLEM TO BE SOLVED: To provide an ion-exchange membrane which has chemical resistant stability equal to that of a perfluorocarbon ion-exchange membrane and has heat resistance for being applicable even in an atmosphere having a high temperature of 100 deg.C or higher; and a method for producing the membrane at a low cost easily. SOLUTION: Both the ion-exchange membrane and the method for producing it are characterized in that a heat resistant polymer having imide bonds is processed into a thin membrane, which is then dipped in a sulfonating agent to sulfonate, wherein the heat resistant polymer is a polyimide derived from biphenyl tetracarboxylic acid with phenylene diamine: or a polyamide imide derived from trimellitic acid or the anhydride with diaminophenyl ether, diaminophenylmethane, or diaminophenylmethane diisocyanate.