| Abstract: | The sulfonated polyetherimide (sPEI) was synthesized by direct sulfonation method using chlorosulfonic acid as a sulfonating agent. Different sulfonation degrees of sPEI was obtained by varying the ratio of PEI to chlorosulfonic acid and reaction time. Then, sulfonated polyetherimide was blended with polyethylene glycol (PEG) and thermally cross-linked in order to achieve high performance proton exchange membrane. It was found that the addition of PEG resulted in a significant increase in porosity and water uptake of the membranes, which favored proton transport at low temperature. The maximum proton conductivity was 11 mS/cm at 75°C for the blend membrane containing 20% PEG. The sulfonation and blend modification of PEI were characterized by attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy. |
