The invention relates to monomers derived from perhalogenated sultones, to a process for their preparation, to the polymers obtained from the said monomers and to their use for the production of ion-conductive materials.The monomers are compounds corresponding to the formula A--CFX--SO.sub.2 Z in which A denotes one groups [sic] R.sup.3 --O--CF.sub.2 -- or R.sup.3 -- or R.sup.1 R.sup.2 N--CO--; Z denotes F, Cl, --OSi(CH.sub.3).sub.3 or an ionic group, Z being other than F when A denotes R.sup.3 --O--CF.sub.2 -- or R.sup.3 --; X denotes F, Cl, H or R.sub.F, X being R.sub.F when A denotes R.sup.3 --; the radicals R.sup.1, R.sup.2 and R.sup.3 are chosen from polymerizable nonperfluorinated organic radicals; R.sub.F is chosen from perfluoroalkyl radicals and perfluoroaryl radicals.The polymers obtained from these monomers can be employed for the production of ion-conductive materials.