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Nanocomposites of polystyrene (PS) with modified CoAl-layered double hydroxide (CoAl–LDH) were preparedviasimple solvent blending method and the effect of CoAl–LDH content on the structural and thermal properties was investigated. The structural and thermal properties of the nanocomposites were characterised by X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy, thermogravimetric analysis and differential scanning calorimetry. The nano-scale dispersion of the CoAl–LDH layers in the PS matrix is verified by the (0 0 3) XRD reflection of the modified CoAl–LDH. The XRD data show that the exfoliated PS/CoAl–LDH nanocomposites can be obtained by controlling the LDH loading of about 5 wt%. TEM analysis also confirms the formation of exfoliated PS nanocomposites with 3 wt% and 5 wt% LDH loading. The thermal degradation temperature of the PS nanocomposite containing 5 wt% CoAl–LDH is found to be 12°C higher than that of pure PS when 50% weight loss is selected as a point of comparison. The glass transition temperature (Tg) of PS nanocomposites is about 14°C higher than that of pure PS. [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]