New sulfonated engineering polymers via the metalation route. I. Sulfonated poly(ethersulfone) PSU Udel® via metalation‐sulfination‐oxidation

Poly(arylene ether)s with Pendant Perfluoroalkyl Sulfonic Acid Groups as Proton‐Exchange Membrane Materials

“…[24] To a solution of polysulfone (PSU) (4.42 g) in anhydrous THF (150 mL) at -76 8C was added butyllithium (2.5 M) until a pale yellow color appeared followed by gradual addition of butyllithium (10 M) (1.5 mL) during 30 min under argon. The reaction mixture was stirred at -76 8C for additional 30 min then the solution was slowly syringed into a dry ice-cold solution of SFBF (12 g, 0.04 mol) in THF (20 mL).…”

Proton Conducting Polysulfone Ionomers Carrying Sulfoaryloxybenzoyl Side Chains

“…This has initiated an extensive search for suitable replacement materials, [5] which has brought thermally and chemically stable sulfonated arylene main chain polymers, e.g., prepared by sulfonation with fuming sulfuric acid, into focus. [6][7][8][9][10] Alternatively, sulfonated polymers can be prepared by direct polymerization using sulfonated monomers [11,12] or by chemical grafting reactions. [13,14] Ionomers having sulfonic acid groups directly attached to the polymer main chain typically show an extensive water uptake above a critical temperature, or above a critical degree of sulfonation, which results in a dramatic loss of mechanical properties.…”

Sulfonated Poly(aryl ether)‐Type Polymers as Proton Exchange Membranes: Synthesis and Performance

“…A new process was developed by Kerres et al for the sulfonation reaction of poly(aryl ether)-type polymers, such as the polysulfone Udel [61]. The sulfonation process is based on the activation of polysulfone by lithiation [62][63][64][65][66][67] [61]. The authors of this study also pointed out that the oxidation step might lead to the loss of IEC and degradation of molecular chains.…”