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Nanoconfinement of a polymer film affords a reduction of the glass transition temperature ( T g ) and effective viscosity (η eff ). Early on, Prof. Tisato Kajiyama pioneered the idea of enhanced polymer mobility at the free surface. This concept is now well established, and accounts for the T g and η eff reductions of thin polymer films. To pay tribute to Prof. Kajiyama's seminal contribution, it is fitting to report in this special issue the use of ultraviolet ozone (UVO) to chemically modify the surface of polymer films and thereby alter their dynamical properties for the first time. Specifically, we show that with a brief exposure time of only 1.0 s under typical UVO treatment conditions, the η eff of polystyrene (PS) films supported by silica changes from decreasing to rapidly increasing as the film thickness is decreased upon the UVO treatment. As such, the tendency of the films to spontaneously rupture on heating is significantly lessened. Considering the simplicity and inexpensiveness of the method, our results demonstrate that UVO treatment is an attractive method to refine the dynamical properties of polymer films and improve their thermal stability.

The significant volumetric change of electrically conducting polymers (ECPs) during the cyclic charging–discharging process causes the capacitance to decrease and electrodes to degrade. Herein we introduce a new strategy for the synthesis of a flexible supercapacitor device based on conducting polyaniline (PANI) nanowires confined within a 10 nm-diameter multiwall carbon nanotube (MWCNT) porous membrane. The PANI nanowires with a diameter of 8 nm and an aspect ratio over 100 are deposited inside the hollow channels of MWCNTs through an in situ electro-polymerization method. The aligned nanostructure of graphitic CNTs provides both protection to the organic polymers and efficient pathways for charge transfer. More importantly, the confined CNT nano-channels suppress the structural change of the PANI chains during multiple charging–discharging cycles and increase the lifetime of the device. Conducting polymers encapsulated inside MWCNTs as such have significant potential to be manufactured into thin, flexible supercapacitor films. The films we made showed a good electrochemical capacitance of 296 F g−1 at a current density of 1.6 A g−1 and considerable stability with the capacitance loss being less than 5% after 2000 charging–discharging cycles.

We demonstrate a novel nano-porous membrane of 10 nm diameter multiwall carbon nanotubes (MWCNTs) filled with thermally sensitive poly(N-isopropylacrylamide) (PNIPAm) hydrogel. High-resolution transmission electron microscopy (HRTEM), micro FT-IR spectroscopy and confocal laser scanning fluorescence microscopy are used to confirm that the MWCNTs are filled with the hydrogel. An improvement in the hydrophilicity of the gel-filled nano-channels is expected to promote the migration of aqueous solutions and the transportation of water. Meanwhile a decrease in ion flux is observed after the nano-pores of MWCNTs are filled with the hydrogel. This new hydrogel filled-CNT material shows potential for nano-chromatography, water purification and use as intelligent ionic channels.