Synthesis and Characterization of a Polystyrene (Cork) Doped by Aluminium Oxide (Al2O3) to Improve Its Optical Properties Using the (UV-VIS) Techniques

Abstract

Cork is considered one of the polymers of very low industrial value and is used only for secondary purposes such as packaging, and it is possible to have any other uses of high value by doping the cork with materials that can change its physical properties, this paper aimed to synthesize and characterize the optical properties of pure Polystyrene (200 grams) Cork, and Polystyrene (200 grams) Cork doped by Aluminum oxide in ratios (0.1 to 0.9) molar, for the preparation of Aluminum oxide, aluminum nitrate (Al(NO3)39H2O)) was used (as a source of Aluminum oxide, provided by (LOBA CHEMIE) company, with a molecular weight of 375.13 and a concentration of 98%, which is a white powder that is soluble in water, it was prepared at a temperature of (80) degrees Celsius for each Samples with different concentrations ranging from (0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9) morality by adding N, N-Dimethylformamide for HPLC and Spectroscopy as an oxidizing agent and precipitant, then by Sol-Gel method at a temperature of 80°C for 60 minutes, samples of doped cork were deposited on glass slides. By using the ultraviolet technique (UV-VIS), the transmittance and absorption spectra were recorded within the wavelength range of (200-800) nm. The results showed that the transmittance decreased with increasing the cork doping percentage. The basic absorption peaks of the cork tends towards the low photon energy (red shift) when increasing the doping rates of Aluminum oxide, while it was tending towards the high energy (blue shift) photon at the cork before doping, and that is through the absorption coefficient values that were calculated from the absorbance spectrum, which is greater than Likewise, the optical parameters of reflectivity, extinction coefficient, and refractive index were calculated. The energy gap of the cork doped by Aluminum oxide is small compared to the energy gap of the pure polystyrene cork. It has been concluded that the Aluminum oxide ratios with different molar values confirm the cause of the energy gap shifts.