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A novel self-oscillating microgels were prepared by copolymerization N-isopropylacrylamide (NIPAAm), organic acid and iron(II) 5-acrylamide-1,10-phenanthroline-bi (1,10-phenanthroline) (Fe(phen)), the catalyst for the Belousov-Zhabotinsky (BZ) reaction. The microgels were characterized by FTIR spectroscopy and scanning electron microscope (SEM). In order to illustrate the self-oscillating mechanism, the static water contact angles of the oxidized and reduced states of self-oscillating microgels were measured. In addition, the self-oscillating behaviors of the microgels were investigated in BZ system under acid-free conditions. Both the redox potential and transmittance self-oscillating were observed at room temperature. [ABSTRACT FROM AUTHOR]

A novel self-oscillation polymer was successfully synthesized by covalently bonding the Fe(phen) catalyst for the BZ reaction onto the poly(N-isopropylacrylamide) polymer chain. The lower critical solution temperatures (LCST) of the polymer chain in the reduced and oxidized states were 37 and 32 °C, respectively. The prepared polymer solution can undergo soluble-insoluble self-oscillation induced by the BZ reaction at constant temperature. [ABSTRACT FROM AUTHOR]

A novel gel was successfully prepared by copolymerization N-isopropylacrylamide(NIPAAm), 2-acrylamide-2-methylpropane sulfonic acid (AMPS) and iron(II) (5-acrylamide-1,10-phenanthroline) bis(1,10-phenanthroline) (Fe(phen)3). The influence of the AMPS feed ratio on the network structure and the swelling ratio was investigated. The chemical structure and interior morphology were investigated by FT-IR spectroscopy analysis and SEM. It was found that the volume and color oscillated with the chemical wave propagation in the gel. And a self-driven conveyer is successfully constructed with the prepared gels acting as both the sheet gel and cargo. When the sheet gel was immersed in the catalyst-free BZ solution, chemical wave propagated in the gel sheet and a cylindrical gel cargo placed on the surface was transported with it. The transport velocity of cargo was investigated and it was related to the BZ substrate concentrations and cargo's diameter. The results are useful in the design of microfluidic devices and autonomously mass-transport systems under mild pH conditions. [ABSTRACT FROM AUTHOR]

A novel Belousov-Zhabotinsky (BZ) gels which were observed volume and color self-oscillating periodically and autonomously in a closed homogeneous solution free of acid without any external stimuli were prepared successfully and the self-oscillating could last more than 3 h. The cross-linked gels are composed of a non-thermoresponsive and biocompatible poly(vinylpyrrolidone) (PVP), acrylic acid (AA) and 5-acrylamide-1,10-phenanthroline bis(1,10-phenanthroline) iron(II) (Fe(phen)3), which act as the catalyst for the BZ reaction. The amplitude of the diameter oscillation for cylindrical gels was about 20 μm to approximately 5% of its initial diameter. The period of the volume oscillation was about 250 s. A moving chemical wave was observed directly propagation across cylindrical gels. The reversible changes in volume and color, the moving chemical wave in the gels have potential applications in the design of microfluidic devices and mass-transport systems under mild pH conditions. [ABSTRACT FROM AUTHOR]