聚四氟乙烯对空气电极防水透气膜性能的影响

The Effects of PTFE on Waterproof Layer of Air Electrode

对以聚四氟乙烯(PTFE)为原料的憎水型空气电极的防水透气膜的制备工艺进行了深入研究.以稳态电流-电压极化曲线的方法对不同防水透气膜电化学性能进行测试,用透气率测量装置对防水膜透气性能进行测试,并用扫描电镜对防水透气膜的表观形貌进行观察,采用以空气电极为阴极,钢板为阳极的电解装置对空气电极寿命进行测试.结果表明:防水透气膜中PTFE的最佳含量在60%～70%范围内,采用热处理工艺后,防水透气膜的孔径分布更加均匀,防水透气膜的透气性能提高,空气电极极化明显减小.电极稳定运行800 h.

Technics for preparing waterproof breathable layer of hydrophobic air-electrode is researched deeply in this article. Performance of different layer is tested respectively by steady-state current-voltage Polarization curve and breath performance is tested by densometer. The scanning electron microscope (SEM) was also used to observe the surface of the waterproof breathable layer. The life of air electrode are tested by electrolytic device which cathode is air electrode and anode is armor plate. The results shows: the best content of PTFE in the waterproof breathable layer is 60% - 70%. After having been heat treated, the layer has better breath performance and the aperture distribution of the layer become more even and polarization of air electrode has decreased markedly. The electrode run steadily after testing 800 hours.