Beads-on-String-Shaped Poly(azomethine) Applicable for Solution Processing of Bilayer Devices Using a Same Solvent

Electrochemical and Optical Properties of D-A-A-A-D Azomethine Triad and Its NIR-Active Polymer

The azomethine TPA-(BTZ)3-TPA with a donor-acceptor-acceptor-acceptor-donor structure has been synthesized and characterized. Azomethine TPA-(BTZ)3-TPA exhibited luminescence properties and a positive solvatochromic effect. Electropolymerization on terminated triphenylamine groups was used to obtain a thin layer of the polyazomethine poly-[TPA-(BTZ)3-TPA]. Further investigation of oxidation/reduction properties of poly-[TPA-(BTZ)3-TPA] via cyclic voltammetry showed that the polymer undergoes two reversible oxidation/reduction processes due to the presence of tetraphenylbenzidine moieties. Electrochromic properties of the polyazomethine poly-[TPA-(BTZ)3-TPA] were investigated via spectroelectrochemistry. It was observed that the polymer in its neutral state is orange, and the color changes to green upon electro-oxidation. The stability of the polymer during multiple oxidation/reduction cycles, response times, and coloration efficiency were also investigated.

Supramolecular organogel formation behaviors of beads-on-string shaped poly(azomethine)s dependent on POSS structures in the main chains

Organogel formation was observed for isobutyl-substituted cage octasilsesquioxane (T₈) in the main-chain type polyazomethines, while precipitates instead of gel formation were observed for phenyl-substituted double-decker-shaped silsesquioxanes (DDSQ)-poly(azomethine)s.

Theoretical Study of the Effect of Different π Bridges Including an Azomethine Group in Triphenylamine-Based Dye for Dye-Sensitized Solar Cells

Ten molecules were theoretically calculated and studied through density functional theory with the M06 density functional and the 6-31G(d) basis set. The molecular systems have potential applications as sensitizers for dye-sensitized solar cells. Three molecules were taken from the literature, and seven are proposals inspired in the above, including the azomethine group in the π-bridge expecting a better charge transfer. These molecular structures are composed of triphenylamine (donor part); different combinations of azomethine, thiophene, and benzene derivatives (π-bridge); and cyanoacrylic acid (acceptor part). This study focused on the effect that the azomethine group caused on the π-bridge. Ground-state geometry optimization, the highest occupied molecular orbital, the lowest unoccupied molecular orbital, and their energy levels were obtained and analyzed. Absorption wavelengths, oscillator strengths, and electron transitions were obtained via time-dependent density functional theory using the M06-2X density functional and the 6-31G(d) basis set. The free energy of electron injection (ΔGinj) was calculated and analyzed. As an important part of this study, chemical reactivity parameters are discussed, such as chemical hardness, electrodonating power, electroaccepting power, and electrophilicity index. In conclusion, the inclusion of azomethine in the π-bridge improved the charge transfer and the electronic properties of triphenylamine-based dyes.

Stretchable Conductive Hybrid Films Consisting of Cubic Silsesquioxane-capped Polyurethane and Poly(3-hexylthiophene)

We fabricated stretchable and electric conductive hybrids consisting of polyhedral oligomeric silsesquioxane (POSS)-capped polyurethane (PUPOSS) and doped poly(3-hexylthiophene) (P3HT). In order to realize robust films coexisting polar conductive components in hydrophobic elastic matrices, we employed POSS introduced into the terminals of the polyurethane chains as a compatibilizer. Through the simple mixing and drop-casting with the chloroform solutions containing doped P3HT and polyurethane polymers, homogeneous hybrid films were obtained. From the conductivity and mechanical measurements, it was indicated that hybrid materials consisting of PUPOSS and doped P3HT showed high conductivity and stretchability even with a small content of doped P3HT. From the mechanical studies, it was proposed that POSS promoted aggregation of doped P3HT in the films, and ordered structures should be involved in the aggregates. Efficient carrier transfer could occur through the POSS-inducible ordered structures in the aggregates.

One-pot strategy for synthesis of open-cage silsesquioxane monomers

A novel synthetic strategy to access POSS monomers has been proposed; one reaction site of an open-cage POSS was capped, and the remaining two silanol groups were functionalized for polymerization. Importantly, the monomer can be obtained by one-pot synthesis without any troublesome isolation process.

Open-cage silsesquioxane necklace polymers having closed-cage silsesquioxane pendants

A novel POSS monomer design has been proposed; a closed-cage POSS was tethered to an open-cage POSS, and the remaining two functional groups were employed for polymerization. The thermal and optical properties of the obtained main-chain type POSS polymers can be widely tuned by the substituents at the corners of the POSSs.