Development of Poly(Arylene ether Sulfone)-Based blend membranes containing aliphatic moieties for the low-temperature decal transfer method

Several hydrocarbon-based polymer membranes have been developed for proton exchange membrane fuel cells; however, their commercialization is hindered by the inefficient fabrication of membrane electrode assemblies (MEAs). In this study, we developed novel sulfonated poly(arylene ether sulfone)s with aliphatic backbones for application in the low-temperature decal transfer method commonly employed in MEA fabrication. Furthermore, the polymer was blended with fully aromatic sulfonated poly(arylene ether sulfone)s with relatively high dimensional stability to enhance membrane durability. The blended membranes exhibited unique morphological structures that improve their performance and long-term stability. One polymer blend (Hex-BP-2) fabricated by low-temperature decal transfer without any additional treatments showed high durability over 1000 wet-dry cycles and high fuel cell performance (579 mW cm⁻²). Such polymer blend membranes are excellent alternatives to perfluorinated sulfonic acid polymers owing to both their high performance and long-term stability.