In the present study, crosslinked poly(vinyl alcohol) (PVA) membranes were prepared using poly(styrene sulfonic acid-co-maleic acid) (PSSA MA) at different crosslinking temperatures. The crosslinked PVA membranes were prepared by varying the content of PSSA MA (5–11 wt%). The PSSA MA was used both as a crosslinking agent and as a donor of the hydrophilic group (–SO₃H and/or –COOH). The crosslinked PVA/PSSA MA membranes were characterized using FT-IR spectroscopy, thermogravimetric analysis (TGA) and investigated in relation to proton conductivity and methanol permeability. The proton and methanol transport decreased with increasing the PSSA MA content. The effect of crosslinking may be more dominant than that of the increase of the number of ionic exchange sites in this system. The proton conductivities and the methanol permeabilities of all the membranes were in the range of 10⁻³ to 10⁻² S/cm and 10⁻⁷ to 10⁻⁶ cm²/s, respectively, in the temperature range of 25–90 ◦C, depending on the crosslinking conditions. ; NRC Pub: yes