**Author details**

338 Smart Actuation and Sensing Systems – Recent Advances and Future Challenges

**Figure 25.** The time series of pH (discontinuous line) and R (solid line).

As for the VP-based self-oscillating polymer chain, we examined the influence of initial substrate concentrations of the BZ reaction on transmittance self-oscillation for the novel poly(VP-*co*-Ru(bpy)3) solution. As a result we noted that the width of the self-oscillation is much affected by the initial concentration of the BZ substrates. In addition, we clarified that the amplitudes of the transmittance self-oscillation is hardly affected by the initial concentrations of the BZ substrates. This tendency was not observed in the case of the AMPS-containing polymer solution. Furthermore, we demonstrated that the period of the transmittance self-oscillation can be controlled by the selection of the initial concentration of

Furethermore we succeeded in clarifying the influence of the initial concentration of the BZ substrates and the temperature on the period of the swelling-deswelling self-oscillation for the novel poly(VP-*co*-Ru(bpy)3) gel. The logarithmic plots of the period against the initial concentration of one BZ substrate under fixed the other two BZ substrates showed the good linear relationships. Moreover, the period of the self-oscillation increased with the increasing the temperature in accordance with Arrenius equation. The maximum frequency (0.5Hz) of the poly(VP-*co*-Ru(bpy)3) gel was 20 times as large as that of poly(NIPAAm-*co*-Ru(bpy)3 gel. Therefore, the period of the swelling-deswelling self-oscillation for the gel can be controllable in wide range by optimizing the initial concentration of the three BZ substrates and the temperature. In addition, we showed that the displacement of the self-oscillation for the gel has the trade-off relationship against the period of the self-

Next, we introduced the new method of generating contraction waves in the functional gel, which controls the reaction diffusion system by flowing the CT solution into the hollow tubular gel. In order to realize this system, the poly(AAm-*co*-AAc) microphase-separated

**4. Conclusion** 

the BZ substrates.

oscillation.

Yusuke Hara\* *Nanosystem Research Institute (NRI), National Institute of Advanced Industrial Science and Technology (AIST), Japan* 

Shingo Maeda *Shibaura Institute of Technology, Japan* 

Takashi Mikanohara, Hiroki Nakagawa, Satoshi Nakamaru and Shuji Hashimoto *Department of Applied Physics, Graduate School of Science and Engineering, Waseda University, Japan* 
