PVA/PAA复合膜电响应特性的研究

通过研究PVA/PAA复合膜红外光谱特性,扫描电镜分析,及电场作用下膜通量的变化,阐明了PVA/PAA复合膜的电响应特性和规律。研究结果表明:制备的PVA/PAA复合膜中PVA与戊二醛已经发生交联反应形成酯键;-COOH基团的离子化是产生电响应的必要条件。随着PAA含量的增加,膜通量也明显的增加,表明体系中离子基团的数量(浓度)能够强烈影响PVA复合膜的直流电响应性;随着电场强度的增大,膜通量增加;在离子强度小于0.01mol/L时,膜通量随离子强度的增加而增加,但当离子强度大于0.01mol/L时,膜通量则呈现下降的趋势。在实验条件下,比较理想电响应条件为PVA∶PAA=1∶1,溶液离子强度为0.01mol/L。

Preparation of PVA/PAA composite membrane and its electrical response

The characteristics and patterns of electric response for prepared PVA/PAA composite membrane were studied by investigating the infrared spectral properties,scanning electron microscopy analysis,and the changes of membrane flux under an electric field.The experimental results showed that for the prepared PVA/PAA composite membrane,PVA and glutaraldehyde cross-linking reaction had occurred and the ester bond was formed:the ionization of-COOH groups was necessary condition for the generation of electro-response.With the increase of PAA content.the membrane flux was also significantly increased,which showed that the number(concentration)of the ionic groups in the system could strongly affect the electric responsiveness of PVA composite membrane;the membrane flux was improved with the increase of the electric field strength;when the ionic strength was less than 0.01mol/L,the membrane flux increased with the increase of electric field strength;when the ionic strength was more than 0.01mol/L,the membrane flux showed decreasing trend with the increase of the electric field strength.Under the experiment situation,the optimum conditions for electric response were:PVA:PAA=1:1,and the solution ionic strength was 0.01mol/L.