PVA-AA-KOH-H2O碱性聚合物电解质的制备与性能研究

Preparation and properties of PVA-AA-KOH-H_2O alkaline polymer electrolytes

采用溶解-铸膜法,制备了聚乙烯醇(PVA)-丙烯酸(AA)-KOH-H2O碱性聚合物电解质膜。为优化电解质膜的性能,研究了成分对电解质膜特性的影响。通过XRD进行物相分析;通过DSC分析了膜的热学特性;通过电化学测试方法测定膜的电导率和电化学稳定窗口。研究显示AA共混可明显改善PVA基碱性聚合物电解质膜的保湿性能和机械性能。KOH和AA可使PVA的结晶度和熔点降低,有利于提高电导率。实验制备的聚合物电解质膜的电导率均可达到10-2S/cm数量级,最大可达0.18S/cm。电导率随膜内KOH、AA、H2O的含量增加而增大;在25～80℃范围内,电导率与温度的关系符合Arrhenius方程,并具有良好的电化学稳定性,电化学稳定窗口达3.6V,可满足大多数器件对电解质的要求。

Poly（vinyl alcohol）-acrylic acid-KOH-H2O alkaline polymer electrolyte membranes were prepared by solution-casting method.In order to optimize properties of membrane,the effect of ingredient on characteristics of it is investigated.The phase constituent in membrane is checked by XRD method and the thermal property by DSC technology.In addition,the ionic conductivity and electrochemical stability are investigated with electrochemical measurement technology.The water retention capacity and mechanical property of PVA based alkaline polymer electrolyte membranes can be improved obviously by blending with AA.Addition of KOH and AA can reduce the crystallinity and melting point of the polymer,which makes for the higher conductivity.The polymer electrolyte membranes in this experiment exhibited a high conductivity,all reached 10^-2 S/cm,and increased with the increase of KOH content,AA content and H2O content.The maximum conductivity is 0.18S/cm.The temperature dependence of conductivity conforms to Arrhenius equation in the temperature range of 25-80℃.The polymer electrolyte showed good electrochemical stability with an electrochemical stability window of about 3.6V.So these alkaline polymer electrolytes can meet the most equipments＇demands for their electrolytes.