Optical and thermal properties of oil shale/polystyrene composites

The optical and thermal properties of polymer composites having a matrix of polystyrene and oil shale as filler with different concentrations have been investigated. The optical spectra were obtained in the UV wavelength range (300--800 nm) using a spectrophotometer. The absorption coefficient and the optical energy gap (Eopt) have been obtained from direct allowed electron transitions in k-space at room temperature. The tail widths of localized states in the band gap (?E) were evaluated using the Urbach-edges method. It was found that both E opt and ?E vary with the concentration of oil shale in the composite. The thermal conductivity of the prepared oil shale/polystyrene composites has been studied as a function of temperature and oil shale content. It was found that the thermal conductivity increases with temperature and oil shale concentration.