A method for preparing a radiation grafted fuel cell membrane with enhanced chemical stability and a membrane electrode assembly

摘要

It is the aim of the present invention to provide a method for preparing a membrane to be assembled in a membrane electrode assembly and a membrane electrode assembly which both have significant mechanical stability and appropriate fuel cell characteristics.;These objectives are achieved according to the present invention by a method for preparing a membrane to be assembled in a membrane electrode assembly, such as a polymer electrolyte fuel cell, comprising the steps of:a) irradiating the base polymer film with electromagnetic and/or particle radiation in order to form reactive centers, i.e. radicals, within the said polymer film;b) exposing the irradiated film to a mixture of monomers amenable to radical polymerization comprising α-methylstyrene and methacrylonitrile in order to achieve the formation of a graft copolymer in said irradiated film.c) Sulfonating the grafted film to introduce sulfonic acid sites providing ionic conductivity of the material.