Preparation and properties on novel flexible conductive materials with PBI substrate

With rapid development of flexible conductive materials, novel flexible conductive materials with better substrate are in great demand. Polybenzimidazoles (PBI) possess excellent comprehensive performance, possibly an optimum substrate for flexible conductive materials. However, the surface of PBI membrane is hydrophobic, hindering attachment of nanowires. This could restrict its application in flexible conductive materials. In this study, hydrophilicity of PBI membrane surface was enhanced with phosphoric acid (PA) doping, as assessed by contact angle measurement before and after doping. Contact angle of PBI membrane decreased from 84° to 28° after PA doping. A series of novel flexible conductive materials with PBI substrates were prepared by dispensing Ag nanowires onto PA doped PBI membrane surface, which were named PA-PBI-Ag. SEM photographs revealed that Ag nanowires were evenly distributed on PBI surface and presented crosslink microstructure, guaranteeing good conductivity of PA-PBI-Ag. Sheet resistance was determined to be 1.2 ohm per square, which remained unchanged after bending 1000 times. PA-PBI-Ag flexible conductive materials can therefore be prepared simply, exhibit good properties, and will have extensive application prospects.