The hybrid antifogging materials poly­(3-aminopropyl)­silsesquioxane (PAPS) and poly­(3-(2-aminoethylaminopropyl)­silsesquioxane) (PAEAPS) were prepared by sol–gel reactions that are autocatalyzed by the amine moieties of the monomers. PAPS and PAEAPS show good film-forming abilities, and the films obtained were found to be uniform and pinhole-free. X-ray diffraction analysis of PAPS and PAEAPS films indicated the formation of ladder-like structures. The PAPS and PAEAPS films exhibit high water uptakes of 34 and 42%, which are 1.2 and 1.5 times that of the typical antifogging polymer poly­(vinyl alcohol) (PVA), respectively. Furthermore, the PAEAPS film exhibits a scratch resistance 4–6 times that of PVA, and a glass substrate bearing a PAEAPS film remained transparent after removal from a refrigerator. Thus, PAEAPS films exhibit high transparency under humidified conditions and show good antifogging ability.

In the field of organic/inorganic hybrid polymers with the application as thermal insulating materials, ethylene-bridged polysilsesquioxane films are promising materials with enhanced thermal insulating properties due to the presence of intramolecular void spaces in their frameworks. With the aim of increasing the content in intramolecular void spaces to further enhance the thermal property of the resulting material, this paper describes the hydrosilylation reaction of hydrodimethyl-silylated oligomethylsilsesquioxane (MSQ-SiH) and octavinyl polyhedral oligomeric silsesquioxane (Vinyl-POSS) to produce a hybrid film with intramolecular void spaces, which was colorless and transparent due to the formation of covalent SiCCSi bonds. As a control experiment, a polymethylsilsesquixane (MSQ) film and an MSQ film containing 5 wt % of Vinyl-POSS (composite film-5) were prepared. Hybrid film-5 (prepared from MSQ-SiH and 5 wt % of Vinyl-POSS) exhibited lower density and thermal diffusivity (1.19 g/cm 3 and 1.21 × 10 −7 m 2 /s) than the MSQ film (1.34 g/cm 3 and 1.36 × 10 −7 m 2 /s) and composite film-5 (1.37 g/cm 3 and 1.58 × 10 −7 m 2 / s). Hybrid film-5 showed a 5% weight loss temperature (T d 5) and a 10% weight loss temperature (T d 10 ) of 382 and 453 °C, respectively, which were lower than those of the MSQ film (T d 5 of 436 °C and T d 10 of 481 °C) and higher than those of composite film-5 (T d 5 of 325 °C and T d 10 of 453 °C). Positron annihilation lifetime technique revealed that the hole volumes estimated from the value of the positronium lifetime component decreased in the order hybrid film-5 > MSQ film > composite film-5. Taken together, the results demonstrate that the thermal insulating property of the polysilsesquioxane film was improved by the formation of intramolecular void spaces around the POSS molecules.

Previously, we synthesized π-conjugated trinuclear metalladithiolene complexes based on benzenehexathiol (J. Chem. Soc., Dalton Trans.1998, 2651; Dalton Trans.2009, 1939; Inorg. Chem.2011, 50, 6856). Here we report trinuclear complexes with a triphenylene backbone. A reaction with triphenylenehexathiol and group 9 metal precursors in the presence of triethylamine gives rise to trinuclear complexes 9-11. The planar structure of 11 is determined using single crystal X-ray diffraction analysis. The ligand-to-metal charge transfer bands of 9-11 move to longer wavelengths compared with those of mononuclear 12-14. Electrochemical measurements disclose that the one-electron and two-electron reduced mixed-valent states are stabilized thermodynamically. UV-vis-NIR spectroscopy for the reduced species of 9 identifies intervalence charge transfer bands for 9(-) and 9(2-), substantiating the existence of electronic communication among the three metal nuclei. These observations prove that the triphenylene backbone transmits π-conjugation among the three metalladithiolene units.

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