Patent ID: 7034082

Claim:
A process for cross-linking sulfonyl groups —SO 2 Y − (M + )A of a sulfonated polymer wherein at least a fraction of the cross-linking bonds bear an ionic charge, the process comprising contacting the polymer with a cross-linking agent allowing the reaction between two sulfonyl groups —SO 2 Y − (M + )A from adjacent polymeric chains to form the cross-linking bonds, wherein the cross-linking bonds are of the type: P—SO 2 (M + )Y − SO 2 -(Q-SO 2 ) r —Y − (M + )SO 2 —P′ wherein P and P′ are the same or different and are part of a polymeric chain; Y is N or CR wherein R is H, CN, F, SO 2 R 3 , substituted or unsubstituted C 1-20 alkyl, substituted or unsubstituted C 5-20 aryl, or substituted or unsubstituted C 2-20 alkenyl, wherein each substituent is independently one or more halogen, and wherein R may have one or more substituent selected from F, SO 2 R, aza, oxa, thia or dioxathia; R 3 is F, substituted or unsubstituted C 1-20 alkyl, substituted or unsubstituted C 5-20 aryl, or substituted or unsubstituted C 2-20 alkenyl, wherein the substituent is selected from one or more halogens; M + is an inorganic or organic cation; Q is a divalent radical C 1-20 alkyl, C 1-20 oxaalkyl, C 1-20 azaalkyl, C 1-20 thiaalkyl, C 5-20 aryl or C 5-20 alkylaryl, each being optionally substituted by one or more halogens, and wherein Q may have one or more substituents selected from oxa, aza, or thia; A is M, Si(R′) 3 , Ge(R′) 3 or Sn(R′) 3 wherein each R′ is C 1-18 alkyl; r is 0 or 1; and the divalent radical and the sulfonated polymer are partially or completely fluorinated.