Self‐Oscillating Gels Driven by the Belousov–Zhabotinsky Reaction as Novel Smart Materials

Abstract So far stimuli‐responsive polymer gels and their application to smart materials have been widely studied; this research has contributed to progress in gel science and engineering. For their development as a novel biomimetic polymer, studies of polymers with an autonomous self‐oscillating function have been carried out since the first reports in 1996. The development of novel self‐oscillating polymers and gels have been successful utilizing the oscillating reaction, called the Belousov–Zhabotinsky (BZ) reaction, which is recognized as a chemical model for understanding several autonomous phenomena in biological systems. The self‐oscillating polymer is composed of a poly( N ‐isopropylacrylamide) network in which the catalyst for the BZ reaction is covalently immobilized. In the presence of the reactants, the polymer undergoes spontaneous cyclic soluble–insoluble changes or swelling–deswelling changes (in the case of gel) without any on–off switching of external stimuli. Potential applications of the self‐socillating polymers and gels include several kinds of functional material systems, such as biomimetic actuators and mass transport surface.