Synthesis and Characterization of a Polystyrene (Cork) Doped by Aluminium Oxide (Al2O3) to Improve Its Optical Properties Using the (UV-VIS) Techniques
Tamador Almardi Albashier,
Mahmoud Hamid Mahmoud Hilo,
Abdalsakhi Suliman
Issue:
Volume 6, Issue 2, December 2020
Pages:
14-20
Received:
30 September 2020
Accepted:
20 October 2020
Published:
19 November 2020
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.
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 (...
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The Temperature Dependence of Optical Texture in Chiral Nematic Liquid Crystal Observed by Polarizing Microscope
Risti Suryantari,
Flaviana Catherine
Issue:
Volume 6, Issue 2, December 2020
Pages:
21-27
Received:
7 November 2020
Accepted:
24 November 2020
Published:
4 December 2020
Abstract: Study the optical-thermal dependence of liquid crystal based on the quantity data of image texture is important to get more information accurately. In this research, the optical-thermal dependence of chiral nematic liquid crystals ink sample was investigated based on the texture and color changes of the sample at various temperatures. The textures of the samples were recorded by the crossed-polarizing optical microscope attached to the hot stage and a camera. The temperature dependence of textures are represented by the hue parameter values taken from the HSV image type. The result obtained from the graph of the increase mean hue parameter against the temperatures was in accordance with the preceding results done by the various techniques. The results show that the higher the temperature of the material, the higher the average hue value. The increase in the hue parameter relates to the color changes of texture from red-dominant to green-dominant. The color difference appeared in various wavelengths represent a diffraction pattern caused by its optically active and the twisted molecular structure. Approaching to the Bragg diffraction equation, the pitch obtained at 0.7 µm. Furthermore, the relation of the different textures and the twist structure of the sample was evaluated. Considering the sample thickness of 100 µm carries out to the conclusion that there are hundreds of twisted nematic liquid crystal molecules in various alignment on a volume space.
Abstract: Study the optical-thermal dependence of liquid crystal based on the quantity data of image texture is important to get more information accurately. In this research, the optical-thermal dependence of chiral nematic liquid crystals ink sample was investigated based on the texture and color changes of the sample at various temperatures. The textures ...
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