PVA-based cation exchange hybrid membranes with multifunctional groups prepared from ternary multisilicon copolymer

► Ternary multisilicon copolymer poly(MA-co-SSS-co-γ-MPS) is prepared. ► Membranes with multifunctional groups (SO3Na, COOH and OH) were prepared. ► Membrane performances for alkali recovery are excellent (UOH = 0.011-0.019 m/h). ► DD performances cannot be well explained by “three phase” membrane structure. ► DD cannot be well explained by WR, IEC and fixed group concentration (CR).