Riikka Mäki-Ontto

Hairy tubes: Mesoporous materials containing hollow self-organized cylinders with polymer brushes at the walls

In this chapter, a route to prepare “hairy tubes” is presented. Hydrogen-bonded supramolecules, based on PS-block-P4VP, self-organize into cylinders in a glassy rigid PS-matrix. Annealing the material and applying oscillatory shear flow increases the macroscopic order of the cylinders. Part of the supramolecular complex, i.e. PDP, can be conveniently washed out using methanol after the structure has been formed. Thus, empty tubes with P4VP “hairs” on the walls are obtained. This simple method allows tailoring the tubes and the transport properties, for example by tuning the block lengths or by chemical modification of the hairs.

Tridirectional protonic conductivity in soft materials

ATR IR spectra were measured on a Fourier transform infrared (FTIR) Perkin-Elmer System 2000 spectrometer equipped with a SpectraTech horizontal ATR cell (60 incident angle, Ge ATR crystal). Titanium dioxide mesoporous films were deposited on ITO glass by the reverse-micellar route and the photosensitizer RuL2(NCS)2 was attached as in [3]. The ureasil precursors were synthesized as in [18]. Synthesis of class II nanocomposite gels using ureasil precursors, their enrichment with the iodine/ iodide couple, and their deposition in a DSPEC was carried out as follows: absolute ethanol (2 mL) was mixed with the ureasil precursor (PP-4000, 2 g). KI (0.5 M) and I2 (0.05 M) were added to the above mixture with stirring at ambient conditions. The mixture was continuously stirred for about 3 h. Then acetic acid (0.35 mL) was added and stirring continued for another 4 h at ambient conditions. At the end of this period, a viscous brown fluid was obtained. A few drops of this solution were applied to the electrode-bearing TiO2 film with attached dye and we placed the second (platinized) electrode on top, simply by pressing the two electrodes together. Connections were made with silver paste and a copper ribbon as seen schematically in Figure 4.