通过溶液共混方法 ,制备了聚偏氟乙烯与聚苯乙烯磺酸 (PVDF_PSSA)、聚偏氟乙烯与Nafion(PVDF_Nafion)两种共混膜 .研究了膜组成对膜电导率和甲醇透过率的影响 .与Nafion 1 1 7膜相比 ,PVDF_Nafion共混膜在Nafion含量为 2 5wt%时 ,电导率σ下降 2个数量级 ,而甲醇透过率P却降低 3个数量级 .若以 (σ/P)为综合指标 ,则PVDF_Nafion共混膜和PVDF_PSSA共混膜的综合性能分别比Nafion 1 1 7膜高约 4 0倍、1 6倍
An attempt was made to modify membranes for direct methanol fuel cells by blending Nafion or polystyrene sulfonic acid (PSSA) with polyvinylidene fluoride (PVDF) from their solutions. The proton conductivity and methanol barrier property as a function of the membrane compositions are discussed. Compared with the Nafion 117 membrane, the PVDF_Nafion blend membranes with 25 wt% of Nafion showed a decrease in the conductivity by about 2 orders of magnitude, and the methanol barrier properties increased about 3 orders of magnitude. If the ratio (σ/P) is adopted to characterize the performance of the membrane, the PVDF_PSSA and PVDF_Nafiion blend membranes are 16 and 40 times better than Nafion 117 membrane.
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