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Organic–inorganic nanocomposites have endured our interest in research, as they possess unique physical and chemical properties in various fields of application. In the present investigation, ZnO nanoparticles and polystyrene/zinc oxide nanocomposite films were successfully synthesized by sol–gel and solution-mixing techniques, respectively. These thin films were prepared with varying concentrations of ZnO, i.e., from 0 to 20 wt%. The thickness of these synthesized films was measured experimentally. These films were characterized to investigate the structural, morphological and thermal properties using Fourier transform infrared spectroscopy, atomic force microscopy, scanning electron microscopy (SEM) and differential scanning calorimetry (DSC) techniques. The roughness of film surfaces has been calculated from Nanoscope analysis software and correlated to the SEM images. The glass transition temperature of pristine and nanocomposite films is observed from the analysis of DSC data. [ABSTRACT FROM AUTHOR]

Low-temperature transmission electron microscopy (TEM) studies were performed on polystyrene (PS, M = 234 K) - Au nanoparticle composite thin films that were annealed up to 350°C under reduced pressure conditions. The composite thin films were prepared by wet chemical approach and the samples were then subsequently spin-coated on a carbon-coated copper grid for TEM measurements. TEM measurements were performed at liquid nitrogen temperatures to reduce the electron-beam-induced radiation damage. The results showed a marginal increase in Au nanoparticle diameter (2.3 nm-3.6 nm) and more importantly, an improved thermal stability of the polystyrene (PS) composite film much above its glass transition temperature. [ABSTRACT FROM AUTHOR]

The effects of SiO2 (amorphous) and TiO2 (crystalline, rutile) fillers on softening point ( Ts), glass transition temperature ( Tg), coefficient of thermal expansion (CTE), and dielectric constant ( ɛ) of zinc bismuth borate, ZnO-Bi2O3-B2O3 (ZBIB) glass microcomposites have been investigated with a view to its use as the white back (rear glass dielectric layer) of plasma display panels (PDPs). The experimentally measured properties have also been compared with those of theoretically predicted values. Both the experimental and theoretical trends of these properties with added filler contents correlate very well. The interaction of fillers with glass which occurred during sintering at 560°C has also been monitored by XRD and FTIR spectroscopic analyses. The microstructures and distribution of fillers in the glass matrix have been analyzed by SEM images. It is observed that the fillers have partially dissolved in the glass at the firing temperature leaving some unreacted filler as residue which results in ceramic-glass microcomposites. In consideration of the desired properties of white back of PDPs, the addition of TiO2 filler to ZBIB glass is found to be more preferable than SiO2 filler. The addition of 10 wt% TiO2 filler yielded Ts, Tg, CTE and ɛ values of 560°C, 480°C, 82 × 10−7/K and 14·6 which are found to meet the desired values of <580°C, <500°C, <83 × 10−7/K and <15, respectively with respect to use of PD200 glass as substrate in PDP technology. [ABSTRACT FROM AUTHOR]