New promising polymer for organic solvent nanofiltration: Oxidized poly (arylene sulfide sulfone)

Polymeric membranes have attracted much interest in recent years for use in organic solvent nanofiltration. This article reports the development of a novel solvent resistant oxidized poly (arylene sulfide sulfone) (PASS) membrane and proposes a new strategy to enhance the solvent resistance of this PASS membrane via improving the rigidity, intermolecular interaction and packing density of polymer chains by a simple oxidation process. The PASS membranes were firstly fabricated by phase inversion, and then a facile green oxidation process was carried out to improve their solvent resistance. The oxidized PASS (O-PASS) membrane was found to exhibit an excellent stability in aggressive solvents, such as DMF and NMP, and endure 98% H2SO4 without sacrificing its filtration performance. In organic solvent nanofiltration (OSN), the O-PASS membranes exhibited a high rejection of dyes such as rose Bengal (RB), erythrosin B (EB), reactive orange 16 (RB16) and Sudan black B (SBB), and a stable filtration performance for 30 h in DMF. Compared to other reported OSN membranes, this membrane showed an exceptionally high solvent permeation. This extraordinary OSN filtration performance, easy fabrication process and the strong solvent resistance, make PASS a very promising polymer in the field of OSN.