Synthesis and characterization of novel cross-linked quaternized poly(vinyl alcohol) membranes based on morpholine for anion exchange membranes

A series of novel cross-linked and quaternized poly(vinyl alcohol) (QPVA) anion exchange membranes were prepared for application in alkaline anion exchange membrane fuel cells. These membranes, with excellent electrical and thermal properties , were prepared via a relatively simple procedure, by using nontoxic and mild 4-methyl-4-glycidylmorpholin-4-ium chloride (MGMC), made in the laboratory, as a quaternization reagent to graft aliphatic morpholine ring units that acted as the fixed charged groups, followed by reacting the remaining unreacted hydroxyl groups with different amounts of bisphenol-A epoxy resin (DGEBA) and alkalization. The reaction products were characterized by nuclear magnetic resonance ( 1 HNMR), Fourier transform infrared (FTIR), elemental analysis , scanning electron microscopy (SEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA) and electrochemical methods . The membranes exhibited good thermal stability below 210   °C. The ionic conductivity can be as high as 5.21   ×   10 −   2   S·cm −   1 at 60   °C in water.