Ag-IPMC物质组分变化及失效机制

Material Component Variation and Failure Mechanism of Ag-IPMC

为了明确IPMC的失效机制,提高其使用寿命,以制备的Ag-IPMC为研究对象,对Ag-IPMC失效前、后的表面物质组分变化进行分析。采用能谱仪对选取的3处新制Ag-IPMC样件表面和5处失效Ag-IPMC样件表面进行能谱分析,分析Ag-IPMC样件失效前后其表面物质组分的变化规律,研究Ag-IPMC表面物质组分变化对运动失效的影响。结果表明:新制的Ag-IPMC样件的表面Ag镀层中几乎没有Ag的氧化物存在,并且Ag镀层的导电性能优良,为基膜内离子的交换提供稳定的电场环境;失效的Ag-IPMC样件表面Ag元素含量降低,在电流作用下镀层中的Ag与O和S发生反应,生成了氧化物和硫化物,使镀层结构产生类似于拉伸断裂的现象,从而增大了Ag-IPMC表面镀层的接触电阻,导致Ag-IPMC失效。

The change of surface chemical components of the prepared Ag-IPMC before and after the failure was analyzed to identify its failure mechanism and prolong its service life.3 points of active Ag-IPMC surface and 5 points of inactive Ag-IPMC surface were scanned by EDS.The influence of surface component change on movement failure was also investigated.Results show that there is almost no Ag oxide in the clad layer of the active Ag-IPMC sample,and the Ag clad layer has an excellent electrical conductivity,thus providing a steady electrical field for the ion exchange in inophragma.However,Ag content of inactive Ag-IPMC surface decreases;Ag in the clad layer reacts with O and S due to the function of current,to generate oxides and sulfides,leading to a phenomenon similar to tensile fracture;therefore,the contact resistance of Ag-IPMC increases,resulting in the failure of Ag-IPMC.