Large deformation adhesion study of polymetric hydrogel under different stimuli

Hydrogels possess excellent and interesting properties that may be harnessed for future applications, especially in soft machines. However, this is not achievable if the adhesion theory of hydrogel is not well understood. This paper aims to develop an adhesion theory of hydrogels based on the Maugis model and large deformation theory. By applying the proposed theory, we predict the mechanical behaviour during the debonding process for both polymeric networks and swollen hydrogels. Furthermore, the proposed adhesion theory is extended to temperature-sensitive hydrogels, salt concentration sensitive gels, and pH-sensitive gels. Extensive parametric studies are carried out to demonstrate the effect of several key parameters which influence the response of hydrogels subjected to different stimuli. We find that different stimuli, such as a change in the temperature, the pH, can be reflected in the debonding process. Finally, by applying a network simulation method and multi particle tracking method, simulation and experiments are conducted to verify the proposed theory. The theoretical prediction matches reasonably well with the simulation and experimental results.