The invention relates to a composite or a composite membrane consisting of an ionomer and of an inorganic optionally functionalized phyllosilicate. The isomer can be: (a) a cation exchange polymer; (b) an anion exchange polymer; (c) a polymer containing both anion exchanger groupings as well as cation exchanger groupings on the polymer chain; or (d) a blend consisting of (a) and (b), whereby the mixture ratio can range from 100% (a) to 100% (b). The blend can be ionically and even covalently cross-linked. The inorganic constituents can be selected from the group consisting of phyllosilicates or tectosilicates.