Influence of conductive network composite thickness and structure on performance of ionic polymer-metal composite transducer

The important role of the nanostructure of conductive network composite (CNC) layers on the performance of ionic polymer-metal composite (IPMC) transducer has been discussed detailedly. IPMC transducers exhibit both electromechanical and mechanoelectrical behaviors. When subjected to an external electric field, electromechanical behavior of IPMC transducers causes an actuation response which can be reversed by alternation of the polarity of the applied field. The same structure, when subjected to an external mechanical force, generates an electrical signal which can be picked up by ordinary electronic. Mechanoelectrical behavior of IPMCs is utilized in stress sensors and structural health monitoring devices. Incorporation of spherical gold nanoparticles (AuNPs) in the CNC layers can significantly improve the electrical conductivity and porosity of the IPMC transducer, which provides an optimum structure to increase the participation of ions in the actuation and sensing behaviors. We have employed the layer by layer (LbL) self-assembly technique to fabricate CNC layers based on AuNPs and poly(allylamine hydrochloride) (PAH) polycation with a controllable thickness in nano and micro ranges; which, when compared with IPMC transducer without CNC layers on both sides of ionomeric membrane, show an improvement in the actuation and sensing performances significantly. Briefly, when applying a voltage across the thickness of IPMC actuator, the net cationic and anionic strains can be enhanced by