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A new type of nanocomposites based on a high performance bisphenol-A phthalonitrile resin and surfacemodified alumina nanoparticles was prepared by a hot compression molding technique. The effect of adding different amounts of the reinforcing phase on the thermal and mechanical properties of the resulting nanocomposites was investigated. Thermogravimetric analysis showed that the starting decomposition temperatures and the residual weight at 8008C were highly improved upon adding the nanofillers. At 15 wt% nanoloading, the glass transition temperature and the storage modulus were considerably enhanced, reaching 3468C and 3.4 GPa, respectively. The tensile strength and modulus as well as the microhardness values increased with the increasing amount of the nanoparticles. The tensile modulus calculations were investigated using Series, Halpin-Tsai, and Kerner models. Haplin-Tsai model was found to reproduce the experimental data with the best accuracy. Estimation of the nanofillers shape factors for both Haplin-Tsai and Kerner models significantly improved the precision of the cited predictive models. The fractured surface of the nanocomposites analyzed by SEM exhibited homogeneous and rougher surfaces compared to that of the pristine resin. Finally, this new kind of nanocomposites is a highly attractive candidate for use in advanced technological applications such as the aerospace and military fields.POLYM. COMPOS., 00:000-000, 2015.

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In the present work, zinc oxide nanoparticles were treated with aminopropyl trimethoxy silane-coupling agent and used as a new kind of reinforcement for a typical high performance bisphenol-A-based phthalonitrile resin. The resulted nanocomposites were characterized for their mechanical, thermal, and optical properties. Results from the tensile test indicated that the tensile strength and modulus as well as the toughness state of the matrix were all enhanced with the increasing of the nanoparticles amount. Thermogravimetric analysis showed that the starting decomposition temperatures and the residual weight at 800°C were highly improved upon adding the nanofillers. At 6 wt% nanoloading, the glass transition temperature and the storage modulus were considerably enhanced reaching about 359°C and 3.7 GPa, respectively. The optical tests revealed that the neat resin possesses excellent UV-shielding properties, which were further enhanced by adding the nanofillers. Furthermore, the fractured surfaces of the nanocomposites analyzed by scanning electron microscope exhibited homogeneous and rougher surfaces compared with that of the pristine resin. Finally, the good dispersion of the reinforcing phase into the matrix was confirmed by a high resolution transmission electron microscope.

A novel ionic conjugated polymer fluorescent probe (IP) containing fluorenyls and imines was synthesized through a simple condensation method for the rapid detection of Cu2+. The probe exhibited a selective quenching response toward Cu2+ over other common metal ions in phosphate-buffered saline (PBS) at a pH of 7. Moreover, the fluorescence intensity of IP was linearly proportional to the concentration of Cu2+ when it ranged from 1 to 10 μM, and the limit of detection for Cu2+ was 0.45 μM. Furthermore, the quenched fluorescence of IP by Cu2+ was recovered after adding amino acids or ethylenediaminetetraacetic acid (EDTA), indicating that the probe could be recycled and is promising to reduce the detection cost of Cu2+ in real samples.