초록 |
As a novel class of proton exchange membrane (PEM) materials for application in fuel cells, crosslinkable sulfonated poly(arylene ether)s were prepared by polycondensation via nucleophilic substitution reaction. The degree of sulfonation (DS) was determined quantitatively by 1H NMR spectrum for sulfonated polymer series. Fourier transform infrared (FT-IR) is a convenient method that has been used to confirm the sulfonic acid group. The thermal stabilities of the sulfonated polymers were characterized by DSC and TGA. Films were prepared by casting solutions of sulfonated polymers dissolved in DMAc on clean glass substrates. The films were examined for ion exchange capacities (IEC), water uptakes, and proton conductivities. IEC increased with sulfonation content and the proton conductivities of films increased with increasing IEC and temperature. |