A palladium-catalyzed aryl C-H bonds activation/acetoxylation reaction utilizing a bidentate system has been explored. This transformation has been applied to a wide array of pyridine and 8-aminoquinoline derivatives and it exhibits excellent functional group tolerance.

A series of novel ultra low dielectric constant soluble organic-inorganic nanocomposites in which nanoscale octa-aminophenyl polyhedral oligomeric silsesquioxanes (octaAmino POSS-Ph8) were covalently linked onto the fluoropoly(ether ether ketone)s (PEEK-CF 3 -COOH) were prepared and characterized. The chemical structures of the polymer matrix and nanocomposites were confirmed by 1 H NMR and FT-IR spectra. The analysis of wide-angle X-ray diffraction (WAXD) and X-ray photoelectron spectra (XPS) indicated that the POSS clusters were successfully incorporated into the polymer matrix and the homogeneous dispersion of POSS cages in the polymer matrix was evidenced by scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS) (Si-mapping). Furthermore, the influence of the incorporation of POSS particles on the properties of nanocomposites is investigated.The dielectric constants of the organic-inorganic nanocomposites were drastically reduced relative to neat PEEK-CF 3 -COOH films and the dielectric constant could achieve as low as 1.71 (1 MHz). Besides, the thermal and mechanical properties of the nanocomposites were significantly improved by incorporation of octaAmino POSS-Ph8 moieties. Meanwhile, the nanocomposite thin films still retained the good transparency.

Poly(vinyl alcohol) (PVA) and poly(tetrafluoroethylene) (PTFE) emulsion were blended with different mass concentrations and the blended spinning solutions were electrospun into composite nanofibers. The influence of the blend ratio of PVA to PTFE and electrospinning technical parameters on the morphology and diameter of the composite nanofibers were investigated. According to the result of thermogravimetric analyzer analysis, the composite membrane was sintered at 390 °C. The membranes were then characterized by differential scanning calorimetry, attenuated total reflection-Fourier transform infrared (ATR-FTIR), and scanning electron microscopy, respectively. The mechanical properties of the membranes before and after sintering were analyzed through tensile testing. The results show that the PTFE porous membranes could be electrospun effectively, thus demonstrating their potential application as filter media.

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