Abstract Two novel poly(arylene ether)s with sulfonic acid groups attached on pendent napthyl rings were prepared from bis(3

5-dimethyl-4-hydroyphenyl)--naphthyl methane via nucleophilic aromatic substitution polycondensation with bis(4-fluorophenyl) ketone and bis(4-fluorophenyl) sulfone

followed by sulfonation with chlorosulfonic acid.The sructrues of polymers were confirmed by 1H-NMR and FTIR.The results showed that the sulfonation position took place only on the pendent naphthalene ring due to the specially designed molecular structure.The sulfonated poly(arylene ether)s can be dissolved in DMAC

DMF

DMSO and other common organic solvents

so they can be cast into smooth and flexible films.The proton conductivity of film 3b can reach 0.042 S/cm at 80 ℃

equal to the conductivity of Nafion 117 in the same condition.In addition

the swelling rate of these polymers is less than 11.5% and the tensile strength is more than 39 MPa.In a word

the films of side-chain-type sulfonated polymers showed high proton conductivity

high mechanical strength

low swelling rate and good oxidation stability

which can meet the requirement of proton exchange membranes.And the two novel poly(arylene ether)s are expected to be used as proton exchange membranes for fuel cells.