Sustained larger-amplitude self-oscillations induced by the BZ reaction involving Fe(phen)3 catalyst

The poly(VP-co-AA-co-CD-co-Fe(phen)3) self-oscillating polymer gels composed of 5-acrylamide-1,10-phenanthroline bis(1,10-phenanthroline) iron(II) (Fe(phen)3), vinyl-pyrrolidone (VP), beta-cyclodextrin (β-CD) and acrylic acid (AA) were synthesized by radical polymerization. The volume, color and the redox potential self-oscillations were observed synchronizing with chemical wave propagation in acid-free conditions. The amplitude of diameter oscillation was about 40 µm to approximately 10% of its initial diameter and that of the redox potential about 125 mV at the optimal conditions. Moreover, the oscillation could sustain several hours. The long-lasting oscillation gels with large amplitude under mild conditions will be useful for the development of biomimetic materials that can undergo self-oscillation without external stimuli in mild conditions.