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In this work, we newly prepared the multi-walled carbon nanotube (MCNT)-grafted poly(N-isopropylacrylamide) (PNIPAM) on their termini. After grafting PNIPAM, MCNTs dispersed well into water. In addition, the synthesized PNIPAM-terminated MCNTs (PNIPAM-MCNTs) were blended with poly(vinylalcohol) (PVA), and a hybrid film was prepared. The hybrid film showed bending actuation in response to infrared laser due to the heat generated by MCNTs.

A composite gel composed of the C₆₀ fullerene derivatives and poly(3,4-ethylenedioxythiophene)(PEDOT) was prepared using a low-temperature organic-solvent process. PEDOT was synthesized inside the C₆₀-PEG gel and formed nanoscale junctions between C₆₀ and PEDOT, which was beneficial for the movement of electrons and holes. The photocurrent was observed by irradiating the C₆₀-PEG/PEDOT gel electrode with UV or simulated sunlight. Therefore, it is expected that the C₆₀-PEG/PEDOT material is applicable for the photoelectric field, such as solar cells.

Calcium alginate gels containing hydroxyapatite were prepared in one step and evaluated with regard to pH dependence and electrochemical property for applying to drug carriers. The composite gels immersed in a pH indicator solution changed its color by applying voltage. By these results, it was revealed that pH alteration of composite gels occurred by electro-osmosis and electrophoresis. Swelling and shrinking of the composite gels were controlled by external stimuli of pH and voltage and the content of hydroxyapatite.

Microrod patterns were fabricated on PDMS sheets utilizing porous silicon wafers as templates. The prepared microrod PDMS surface showed high water and oil contact angles. To discuss the mechanism, theoretical contact angles were calculated utilizing Wenzel model and Cassie-Baxter model, and compared with the measured values. Furthermore, it was confirmed that the microrod PDMS surface has self-cleaning property.

Assembly of poly(acrylic acid) (PAAc) gel particles with DNA–ethidium bromide (EtBr) complexes was synthesized and the pH-sensitivity was evaluated for application in optical-sensor devices. The swelling ratio of the assembly was regularly changed with pH and the response speed of the assembly was approximately the same as the gel particles. The great increase in pH-sensitivity of the assembly was assumed to be induced by the porous structure. The fluorescence intensity was changed corresponding to the volume alteration of the assembly. The assembly could quickly detect the pH in the surrounding as an optical-signal.

Poly(acrylic acid) (PAAc) gel particles with DNA–ethidium bromide (EtBr) was synthesized and pH-sensitivity and fluorescence property were evaluated for applying to optical micro-pH sensor. Swelling ratio of PAAc gel particles with DNA–EtBr complexes were regularly changed with pH and the gel particle responded to pH for about 60 s. Furthermore, fluorescence intensity of PAAc gel particles with DNA–EtBr complexes were detected with high-sensitivity and changed in response to pH as shown in figure (The left shows the gel particles in pH 2.1 and the right shows in pH 11).