We have revealed the kinetic advantage of the aza-Wittig polymerization over the conventional diamines/dialdehydes polycondensation system for the effective preparation of end-functionalized π-conjugated poly(azomethine)s. The synthesized polymers P1 and P2 possess hexyl groups and POSS units at the chain ends, respectively. Both polymers were highly soluble in common organic solvents including CHCl3, CH2Cl2, THF, benzene, and toluene at room temperature. The thermal stability of POSS-modified poly(azomethine) P2 (temperature of 10% weight loss; T 10 = 381 °C) was high as compared to that of poly(azomethine) without POSS units P1 (T 10 = 372 °C) because of the siliceous bulky POSS segments at the chain ends. Further, UV−vis absorption study in dilute CHCl3 solution (1.0 × 10−5 M) demonstrated that both polymers had the same absorption maxima at 454 nm, resulting from the extension of the π-electron delocalization length of both polymers via the π-conjugated poly(azomethine) backbone. In the film state, UV−vis absorption spectra, fluorescence quantum yields (ΦF), XRD patterns, and TEM images supported that bulky three-dimensional POSS groups at the chain ends effectively suppress intermolecular aggregations of the individual poly(azomethine).

π-Conjugated polymers capped with a boronic acid end-functional group were synthesized by chain-growth Suzuki-Miyaura polycondensation. The obtained polymers were reacted with a π-stacked-polymer scaffold, developed in our previous work. Despite their bulkiness, the conjugated polymers were efficiently introduced into the polymer scaffold. The spectroscopic and optical characterization of the obtained graft polymers in the solid state revealed that the original π-conjugated polymers were stacked in a single polymer chain. Although excluded volume effects prevented significant intermolecular interactions between the polyfluorenes, the introduced polythiophenes formed intermolecular π-stacked structures. Direct observations of the obtained graft polymers showed that the graft polymers self-assembled into the spherical or fiber structures depending on the introduced polymers, whereas no ordered structures were formed by the same polymers before the polymer reaction.

An optically active pi-conjugated poly(azomethine) can be self-assembled into nanometer-sized fibrous architectures with a unique optical activity in the film state, whereas its corresponding racemic analogue did not show any distinct self-assembling properties.

No abstract

No abstract

Conjugated microporous polymers (CMPs) are prepared from disubstituted and tetrasubstituted [2.2]paracyclophane monomers by a Sonogashira-Hagihara coupling. The polymers obtained exhibit a type I nitrogen gas adsorption profi le and H4-like hysteresis loops, indicating that the [2.2]paracyclophane-containing CMPs possess slit-like mesopores. Their Brunauer-Emmett-Teller surface areas are estimated to be above 500 m 2 g − 1 . The step and stacked structure of the [2.2]paracyclophane unit affects the morphology of the polymers because of the contribution of two-dimensional expansion of the poly mer network.

No abstract

No abstract