pH-Sensitive Hydrogel Bilayers: Investigation on Transient Swelling-Induced Bending through Analytical and FEM Approaches

pH-responsive hydrogels are recognized as versatile sensors and actuators due to their unique time-dependent properties. Specifically, pH-sensitive hydrogel-based bilayers exhibit remarkable bending capabilities when exposed pH-triggered swelling. This study introduces a semi-analytical technique that combines non-linear solid mechanics with ionic species transport investigate the behavior of such bilayers. The is validated through numerical simulations, exploring influence kinetic geometric properties on bilayer behavior. results highlight significance interfacial region, particularly in configurations lower hydrogel ratios, which susceptible rupture. also uncovers benefits layer ratio improving swelling rate final deflection, stronger effect observed presence buffer solution. Additionally, compressibility elastomer contributes durability bent shape. These findings enhance our understanding offer valuable insights for design optimization diverse applications.