Asymptotic analysis of compression sensing in ionic polymer metal composites: The role of interphase regions with variable properties

Ionic Polymer Metal Composites (IPMCs) consist of two noble metal electrodes plating an electroactive polymeric membrane, referred to as ionomer, which is electroneutralised by a solvent including mobile ions. The IPMC manufacturing leads thin interphase regions next the electrodes, so-called Composite Layers (CLs), in atoms occupy interstitial sites within ionomer. In this work we extend previous efforts our group on compression sensing include important effect CLs, where large variations electrochemical properties occur. application through-the-thickness displacement shortcircuit electric response, here assumed be governed linearised modified Poisson-Nernst-Planck (PNP) system partial differential equations (PDEs), solved for time-evolving potential and ions concentration functions field evaluated through linear momentum balance. variation material CLs requires simultaneous integration governing PDEs three regions: membrane CLs. To purpose, resort perturbative method matched asymptotic expansions. Except numerical inverse Laplace transform, allows us obtain analytical solution establish equivalent circuit model elucidating main features behaviour. We validate discuss comparison with finite element analyses, whereby also numerically solve nonlinear modified PNP systems fully coupled balance accounting stresses. finally provide some insight into role behaviour, assessing its sensitivity key parameters. expect obtained results aid design optimised sensors.