MODELING OF THE ELECTROMECHANICAL RESPONSE OF IONIC POLYMER TRANSDUCERS BY MEANS OF STREAMING POTENTIAL MECHANISM

摘要

A model for the electromechanical sensing response of ionic polymer transducers (IPTs) by means of a streaming potential mechanism is presented. It is argued that incomplete pairing of covalently attached pendant ionic groups with their electro-neutralizing counterions establishes the existence of a flowing electrolyte within the ionic polymer. This electrolyte exists in the hydrophilic phase of the otherwise hydrophobic material. The streaming potential is generated as the electrolyte flows past electroded regions interspersed within the hydrophobic phase. The model is developed for a recently argued parallel nanochannel morphology in Nafion® membrane, but is applicable to any two-phase ionic polymer morphology. Further, while this preliminary study considers only the bending mode, the proposed mechanism is readily adaptable to the other three modes of sensing (tension, compression, and shear).