Transport modeling in ionomeric polymer transducers and its relationship to electromechanical coupling

dc.contributorVirginia Tech. Center for Intelligent Material Systems and Structuresen
dc.contributorUniversität Stuttgart, Institut für Statik und Dynamik der Luft-und Raumfahrtkonstruktionenen
dc.contributor.authorWallmersperger, Thomasen
dc.contributor.authorLeo, Donald J.en
dc.contributor.authorKothera, Curt S.en
dc.contributor.departmentCenter for Intelligent Material Systems and Structures (CIMSS)en
dc.description.abstractIonomeric polymer transducers consist of an ion-conducting membrane sandwiched between two metal electrodes. Application of a low voltage (< 5 V) to the polymer produces relatively large bending deformation (> 2% strain) due to the transport of ionic species within the polymer matrix. A computational model of transport and electromechanical transduction is developed for ionomeric polymer transducers. The transport model is based upon a coupled chemoelectrical multifield formulation and computes the spatiotemporal volumetric charge density profile to an applied potential at the boundaries. The current induced in the polymer is computed using the isothermal transient ionic current associated with surface charge accumulation at the electrodes induced by nonzero volumetric charge density within the polymer. The stress induced in the polymer is assumed to be a summation of linear and quadratic functions of the volumetric charge density. Euler-Bernoulli beam mechanics are used to compute the bending deflection of the transducer to an applied potential. The diffusion coefficient and permittivity of the polymer is identified from the measured current density to a step change in the applied potential. A comparison between the measured data and the predicted response demonstrates that this model accurately predicts the current discharge due to the applied potential at voltages over the range of 50-500 mV. Furthermore, the measured strain response is accurately predicted by determining the two parameters of the mechanics model that relates volumetric charge density to induced stress. The coupled model with parameters identified from the step response analysis is used to predict the harmonic response of the current and the bending strain. Comparisons between measured data and simulations illustrate that the coupled transport-mechanics model accurately predicts the magnitude and trends associated with the current response and strain output. Excellent agreement is obtained at excitation periods above approximately 1 s while good agreement is obtained at longer excitation periods. The transport model highlights the importance of the asymmetry that develops at large applied potentials and long excitation periods in the volumetric charge density due to the fixed anionic species in the polymer. (c) 2007 American Institute of Physics.en
dc.description.sponsorshipNational Science Foundation (U.S.). CAREER Award - Contract/Grant No. CMS-0093889en
dc.format.extent10 pagesen
dc.identifier.citationWallmersperger, Thomas, Leo, Donald J., Kothera, Curt S. (2007). Transport modeling in ionomeric polymer transducers and its relationship to electromechanical coupling. Journal of Applied Physics, 101(2). doi: 10.1063/1.2409362en
dc.publisherAmerican Institute of Physicsen
dc.rightsIn Copyrighten
dc.subjectCarrier densityen
dc.subjectElectric measurementsen
dc.titleTransport modeling in ionomeric polymer transducers and its relationship to electromechanical couplingen
dc.title.serialJournal of Applied Physicsen
dc.typeArticle - Refereeden


Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
781.54 KB
Adobe Portable Document Format