质子交换膜冻结温度的理论与实验研究

Theoretical and Experimental Investigation in Freezing Temperature of Proton Exchange Membrane

本文理论推导出全氟磺酸膜中水的冻结温度与摩尔含水量λ之间的关系式,并采用示差扫描量热法通过实验测试不同水含量下Nafion211膜的冻结温度。结果表明:Nafion211膜的冻结温度随水含量的增大而升高.当膜中水总含量λ<7时,膜中水的冻结温度下降到-15℃以下;而当λ<20时,膜中水的冻结温度低于-20℃。理论计算与实验测试数据十分吻合。

The relations between freezing temperature and the water content(λ) of the perfluorinated membrane are deduced theoretically,and the freezing temperatures of Nafion 211 membrane with different water contents have been tested experimentally by using Differential Scanning Calorimeter(DSC).The results show that,the freezing temperature of Nafion 211 membrane increases with the increase of water content.While λ is less than 27,the freezing temperature falls below-15℃,whereas the freezing temperature falls below-20℃ when λ is less than 20.The experimental data agree well with the theoretical analysis.