Most hydrogels exhibit coupled chemo-mechanical behaviors when in an aqueous environment with changing salt concentrations. This work presents a theoretical framework and a numerical procedure to describe the coupled mechanical deformation and solvent diffusion of such ion-sensitive hydrogels. A new variational formulation for the coupled governing equations is formulated by implementing the coupled formulations in a finite element procedure in Eulerian frame and further the time-dependent concurrent process of mechanical deformation and solvent diffusion is numerically investigated. The proposed numerical method is demonstrated by analyzing several chemo-mechanical coupling phenomena of initially-swollen hydrogels, such as transient free-swelling and indentation with a spherical punch. The results show that the present model is capable of simulating transient free-swelling and solvent migration in such smart materials subjected to externally-applied mechanical forces.

Date Published: 12 April 2012
PDF: 9 pages
Proc. SPIE 8409, Third International Conference on Smart Materials and Nanotechnology in Engineering, 840915 (12 April 2012); doi: 10.1117/12.924032

Published in SPIE Proceedings Vol. 8409:
Third International Conference on Smart Materials and Nanotechnology in Engineering
Jinsong Leng; Yoseph Bar-Cohen; In Lee; Jian Lu, Editor(s)