In this study, intercalated/exfoliated polystyrene (PS)/organoclay nanocomposites containing different concentration of organoclay have been prepared via solvent blending method, using xylene as a solvent. Some resulting intercalated nanocomposites are transformed to exfoliated nanocomposites by increasing the refluxing temperature or refluxing time for a constant organoclay loading. The X-ray diffraction results reveal the formation of intercalation/exfoliation of organoclay in the PS matrix. The Fourier transform infrared spectroscopy and transmission electron microscopy results confirm the presence of nanomaterial in PS/organoclay nanocomposites. Completely exfoliated nanocomposites are achieved by decreasing the content of organoclay and elongating the refluxing temperature or refluxing time. Thermogravimetric analysis data show that the PS/organoclay nanocomposites have significant enhanced thermal stability. When 50% weight loss is selected as a point of comparison, the thermal decomposition temperature (T d ) of the exfoliated PS/organoclay nanocomposites with 7 wt % of organoclay is 17 C higher than that of pure PS. Thermal decomposition temperature of exfoliated PS/organoclay nanocomposites is better than that of intercalated nanocomposites for a constant organoclay loading. The glass transition temperature (T g ) of PS/organoclay nanocomposites is $ 7.1-8.6C higher than that of pure PS. The thermal degradation activation energy of the nanocomposites is determined via Coats-Redfern method. The improvement of thermal stability of nanocomposites is also confirmed by increasing the activation energies (E a ) and the integral procedural decomposition temperature. Criado method is finally used to determine the degradation reaction mechanism of various samples. The water uptake capacity of PS/organoclay nanocomposites is negligible when compared with pure PS.

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Nanocomposites of polystyrene (PS) with modified CoAl-layered double hydroxide (CoAl-LDH) were prepared via simple 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 (T g ) of PS nanocomposites is about 14 C higher than that of pure PS.

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