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

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.