title: Modeling and analysis of pH-electric-stimuli-responsive hydrogels.
abstract: A multiphysics model is presented in this paper, called the multi-effect-coupling pH-electric-stimuli (MECpHe) model, for analysis of smart hydrogels responding to the stimuli of solution pH coupled with electric voltage, when the hydrogels are placed into pH buffer solution subject to an externally applied electric field. The MECpHe model considers the chemo-electro-mechanical multiphysics effects and formulates the fixed charge density with the coupled effect of buffer solution pH and electric voltage. The model is formulated mathematically by a set of nonlinear partial differential governing equations for predicting the displacement and the swelling ratio, as well as the average curvature of hydrogel strip, and for simulating the distributive profiles of diffusive ionic species concentrations and the electric potential, as well as the fixed charge density. The model is validated by the comparison of the present computation results with experimental data extracted from open literature. The steady-state simulation of the smart hydrogels is then conducted for the pH-electric-coupled stimuli. The influences of the externally applied electric voltage are discussed in detail on the distributions of diffusive ionic species concentrations, the displacement, the swelling ratio and the average curvature of the hydrogel strip.
authors.affiliation: Department of Mechanical Engineering, National University of Singapore, 10 Kent Ridge Crescent, Singapore 119260, Republic of Singapore.
authors.forename: Rongmo
authors.initials: R
authors.lastname: Luo
authors.forename: Hua
authors.initials: H
authors.lastname: Li
authors.forename: Khin Yong
authors.initials: KY
authors.lastname: Lam
mesh_terms: D001703:Biophysics; D002021:Buffers; D004563:Electrochemistry; D020100:Hydrogels / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008962:Models, Theoretical
chemical_list: D002021:Buffers; D020100:Hydrogels