Preparation and properties of sulfonated poly(phenylene arylene)/sulfonated polyimide (SPA/SPI) blend membranes for polymer electrolyte membrane fuel cell applications

► We synthesized a series of blend membranes based on a novel type of sulfonated poly(phenylene arylene)s (SPAs) and sulfonated polyimide (SPI). ► The performances of the blend membranes were significantly improved comparing with either pure SPA or pure SPI membranes. ► The anisotropic proton conductivity ratio (σ⊥/∥) of the membranes in 60 °C water was in the range of 0.85-0.90, closing to that of Nafion 112 and being higher than that of SPI.