| abstract |
A cationic copolymer comprises the divalent monomer units: wherein: each Ar1 independently represents phenylene; each L independently represents a direct bond or wherein each R1 independently represents an alkyl group having 1 to 4 carbon atoms, and each R2 independently represents an alkylene group having from 1 to 6 carbon atoms, and each Z− represents a non-interfering anion; each Ar2 independently represents an optionally substituted divalent aryl ring, with the proviso that if L represents a direct bond, then Ar2 represents an optionally substituted cationic divalent aryl ring accompanied by Z; each R3 independently represents H or an alkyl group having 1 to 6 carbon atoms; and each D independently represents a direct bond or Ar2, wherein adjacent D and L are not both direct bonds, and wherein if L is a direct bond, then D is Ar2. The cationic copolymer can be free-radially cured and used in a membrane. |