Chemically Fuelled Self-Regulating Gel-to-Gel Transition

Abstract

Artificial self-regulating materials can be prepared by exploiting fuel-driven pathways. Dynamic covalent bonds are formed and broken reversibly under mild reaction conditions. Herein, we utilise this concept to programme a system that can undergo a fuel-driven self-regulated gel-to-gel transition. The reaction between the gelator and the fuel resulted in a change in chemical structure of the gelator that initially causes a transition from a solution to gel state by co-assembly. With time, the intermediate complex collapses, re-forming the gelator structure. However, the gel does not collapse. This method allows us to prepare gels with improved mechanical strength. Unlike conventional gel-to-gel transitions, exploitation of dynamic covalent chemistry provides an opportunity to access materials that cannot be prepared directly under similar final conditions.