Multiphysics modeling of electrochemomechanically smart microgels responsive to coupled pH/electric stimuli.

A multiphysics model is developed to simulate the responsive behavior of smart pH-/electric-sensitive hydrogels when immersed into pH buffer solution and subjected to an externally applied electric field, which is termed the MECpHe model. Comparison with experimental data shows the MECpHe model to be accurate and stable. The influence of the externally applied electric voltage is discussed with respect to the distribution of diffusive ionic species and the displacement of the hydrogel strip. The influences of initial charge density and ionic strength on the swelling ratio and the bending deformation of the microgel strip are studied.