A partially fluorinated and sulfonated poly(arylene sulfone) (SPSO) was successfully synthesized via nucleophilic polycondensation of 2,2-bis(4-fluorophenyl)hexafluoro-propane with 4,4'-thiobisbenzenethiol (TBBT). In a second step, the prepared poly(arylene sulfide) was oxidized to SPSO. The polymer was blended with the polybenzimidazole PBIOO (R) to obtain a mechanically stable membrane. This film was compared with other polymer blends, which were synthesized in our group in the last years. We were especially interested in the influence of different bridging groups such as ether, ketone, and sulfone groups. The affect on properties such as water uptake (WU), thermal stability, proton conductivity, and oxidative stability were analyzed in this work. Additionally, the blend membranes were characterized by gel permeation chromatography. The novel SPSO blend shows a high molecular weight, and its blend membrane with PBIOO has an excellent onset of -SO3H group splitting-off temperature (T-SO3H,T-onset) of 334 degrees C. The proton conductivity amounts to 0.11 S cm(-1), and the water uptake reaches 30%. (C) 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 49: 1919-1927, 2011