Temperature-Mediated Controllable Adhesive Hydrogels with Remarkable Wet Adhesion Properties Based on Dynamic Interchain Interactions

Abstract

With the increasing demand in fields such as wearable sensors, soft robotics, tissue engineering, and wound dressings, the development of hydrogels with strong adhesion in wet environments has become a critical focus of research. However, most existing adhesive materials lack the ability to transition rapidly and reversibly between the adhesive and nonadhesive states, and their adhesion is often limited to a single wet environment. In this study, a smart interfacial adhesive hydrogel with tunable adhesion properties across diverse liquid environments is presented. By tailoring interchain interactions and leveraging electrostatically induced traction between hydrophilic and hydrophobic chain segments, the hydrogel achieves reversible adhesion modulation in response to temperature changes while maintaining strong wet adhesion. Notably, its adhesive strength at elevated temperatures (45 °C) is approximately three times greater than at lower temperatures (5 °C). The adhesive hydrogel exhibits an adhesive strength of 227 kPa in aqueous environments and 213 kPa in oil-containing environments. This innovative design strategy enables the hydrogel to exhibit broad switchable, and dynamic wet adhesion capabilities, unlocking significant potential for a wide range of applications.