Solvent‐Induced Dynamic Bond Regulation for Constructing Adaptive Lubricating Hydrogels with Switchable Tribological Performance and Environmental Adaptability

Abstract

AbstractAdaptive lubricating hydrogels (ALH) show promise for reducing friction and energy consumption in various industrial applications. However, retarded switchable tribological performance and poor environmental adaptability limit their integration into application devices. Herein, a dynamic bond regulating strategy based on solvent conversion for producing an ALH with highly switchable tribological performance and decent environmental tolerance is proposed. By incorporating dynamic B─O bonds into the sodium alginate (SA) framework, these bonds transition between associative and dissociative states, facilitated by solvent conversion between glycerol and ethanol. This process modulates the mechanical modulus of the SA network, allowing for achieving highly switchable tribological performance. Furthermore, the inclusion of glycerol not only as a modulus regulator but also serves as an antifreeze component to impart the ALH with superior antifreeze and heat resistance properties, thus allowing the ALH to demonstrate excellent environmental adaptability. As a result, the resulting ALH exhibits highly switchable lubrication behavior, with a dynamically adjustable coefficient of friction (COF) between 0.022 and 0.157, and maintains consistent lubrication performance under a harsh environment (−40–60 °C), representing the state‐of‐the‐art in reported ALHs. This advancement allows for the development of intelligent brake devices (IBD), demonstrating potential applications in controlling drone speed.