Modeling of Nafion-Pt composite actuators (ICPF) by ionic motion

Abstract

In this paper, a white-box model of Nafion-Pt composite actuators considering the following physical phenomena is proposed: 1) ionic motion by electric field, 2) water motion by ion-drag, 3) swelling and contraction of the membrane, 4) momentum effect, 5) electrostatic force, and 6) conformation change. Computer simulation showed the following results. 1) The simulated motions agreed with experimental results improving the accuracy in comparison with the conventional models, especially on the time of the maximum displacement. 2) The nonlinear relation between input voltage and the maximum displacement was explained.

Dynamic model of ion and water transport in ionic polymer-metal composites

“…The first frictional model was introduced by Tadokoro to IPMCs in 2000, 9 where cations together with the hydrated water migrate from the anode to the cathode driven by the electrostatic force. The electrostatic force is balanced by the frictional force and the diffusion force induced by the concentration gradients.…”

“…6 a Email: hlchen@mail.xjtu.edu.cn Later he made a review of IPMCs models and classified them as three categories, physical model, empirical model and grey box model, and only the first of which is discussed here. 7 In 2000 De Gennes, 8 Tadokoro 9 and Nemat-Nasser 10 proposed three representative kinds of models respectively for IPMCs. IPMC is considered as a homogeneous triphasic material including mobile cations, water molecules and polymer network.…”

Modeling the electrical impedance response of ionic polymer transducers

“…Nemat-Nasser et al [26][27][28] have proposed that actuation occurs due to the uptake of water at the interface between the polymer and the metal electrode. 26 In contrast to the work by de Gennes et al 24 and Tadokoro et al 25 the models by NematNasser et al 26,27 do not explicitly include water motion and hydraulic pressure gradients as state variables. An ionic cluster model of the base material provides the basis for modeling the electromechanical transduction between charge distribution and mechanical deformation.…”

“…Their model parameters are the electric conductivity of the material, hydraulic permeability, and a cross-coupling term that models transduction between water flow and the flow of charge. Tadokoro et al 25 have proposed another model based upon ionic motion within the polymer. In the Tadokoro model, electromechanical transduction is attributed to the forces imposed upon the ions as they migrate through the polymer due to an imposition of electric field.…”

“…Beyond the grey box models of de Gennes et al 24 and Tadokoro et al, 25 a separate class of models have been developed using a field approach based upon the micromechanics and electrostatics of the ionic polymer membrane. Nemat-Nasser et al [26][27][28] have proposed that actuation occurs due to the uptake of water at the interface between the polymer and the metal electrode.…”