Preparation and Characterization of Acid-Acid Blend Membranes for Direct Methanol Fuel Cell Applications

摘要

Acid-acid blend membranes were successfully prepared using two types of sulfonated poly(arylene ether sulfone) random copolymers with various ratios (SPAES-BP and SPAES-HPF). The blend membrane properties were investigated using proton nuclear magnetic resonance, thermogravimetric analysis, water uptake, methanol permeability, and proton conductivity measurements. The morphology of the blend membranes varied according to the SPAES-HPF ratio in the blending solution and the nanosized dispersion of the SPAES-HPF in the SPEAS-BP affected the improvement of acid-acid blend membrane properties. Consequentially, the water uptake and dimensional change decreased while the proton conductivity increased in the blend membranes involving a small amount SPAES-HPF compared with that of the SPAES-BP. For the direct methanol fuel cell performance, the power density of SPAES-BP(90)/SPAES-HPF(10) showed an enhancement of 145 mW/cm~2 over that ofNafion 115 (132 mW/cm~2). Keywords: acid-acid blend membrane, sulfonated poly(arylene ether sulfone), DMFC, phase separation.