Dispersed Association of Single-Component Short-Alkyl Chains toward Thermally Programmable and Malleable Multiple-Shape Hydrogel

In pursuit of intelligent hydrogel-based devices, it is imperative to concurrently enhance the shape programmability and customization of hydrogels in order to realize sophisticated actuation and implantation. Until now, multiple temporary shapeshifting of hydrogels has required either multiple external stimuli or distinct thermal-transition phases. In addition, reprocessing the permanent shape of hydrogel mostly relies on the change in their components. These complex prerequisites present challenges to programmability and customization of application-related shapes for hydrogels. This paper reports a type of thermally programmable and malleable multiple-shape hydrogel. The network of this hydrogel is solely composed of a type of polyvinyl alcohol derivative, which is synthesized by substituting hydroxyl groups of polyvinyl alcohol with single-component octyl chains. Through water-vapor exchange and heating in water, these single-component octyl side chains form dispersed clusters with a large strength gr...