Adaptive Polymer Networks: A Leap from Smart to Life-Like Systems

Abstract Stimuli-responsive polymers are functional materials that convert environmental stimuli into programmed changes in material properties. The use of these soft materials in numerous applications, such as soft robotics and functional devices, is often founded on their ability to mimic the functions of biological systems. However, many of these stimuli-responsive polymers have been studied thus far as “smart” materials with predetermined, reversible responses that lack the dynamic adaptability that is characteristic of biological systems. Moving toward life-like “adaptable” responses will require thoughtful consideration of multifunctionality, integrated feedback loops, and out-of-equilibrium behavior in the programming of stimuli-responsive polymers. Notably, an immense design space for integrating these functionalities has been explored, providing tools for advancing the design of adaptive behavior in responsive polymer networks. In this Viewpoint, we discuss the broad range of tools that are currently accessible for programming stimuli-responsive behavior spanning from the molecular to the polymer network scale and with respect to macroscopic processing of the material. We discuss how these principles provide a foundation for incorporating increasingly life-like capabilities in stimuli-responsive materials, establishing a toolkit for transforming stimuli-responsive polymers from predictable smart materials into dynamic, adaptive materials that more closely emulate the functionality of biological systems.