الفهرس 
Introduction and literature surveyOnly 14 pages are availabe for public view
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Abstract
The present thesis is divided to two parts which includes two systems, respectively. The first system is entitled: ”The effect of gelatin doping on the physical, structural and optical properties of PVA/PVP blend films”. Some measurements carried out before and after heat treatment. While the second one which now published entitles: ”Chitosan filler effects on the experimental characterization, spectroscopic investigation and thermal studies of PVA/PVP blend films” has been studied in the present system. In case of PVA/PVP blend doped with gelatin system structural, optical, thermal and morphological studies were performed on pure PVA/PVP (50/50) blend and PVA/PVP blend doped with different concentrations of gelatin X (0.0, 20, 40, 60, 80, and 100 wt%) using casting method. The prepared films were investigated by different techniques. All techniques demonstrate the complexation between gelatin and the polymers blend. There were some changes in the IR absorption bands position and its intensities. The effect of gelatin on shape of conjugated bonds is also observed after heating. UV-Vis analysis revealed that the values of the optical energy band gap are changed with increase gelatin content. This indicates that there is a charge transfer complexes arise between the polymer blend and gelatin. Scanning electron microscope (SEM) images of different concentrations of films revealed that by increasing gelatin content, an interesting pattern was observed for X= 40% and a highly condensed number of small granules, nearly equal in size in regular way. The X-Ray diffraction (XRD) showed that heights of the main halos at scattering angle of 2θ ≈20º rapidly decreased up to X=20% and above which an increase in the height of the halo, this is due to an increase in the degree of crystallinity with respect to X=20%. After heat treatment films XRD, scans become more sharp, this indicates that an increasing in the degree of crystallinity of the prepared films after heat treatment. The Thermogravimetric analysis (TGA) showed that major weight loss is observed in the range of 250 – 490 °C for all the prepared samples. This may be correspondent to the structural decomposition of the polymer blends and their complexes. The position of Tg for PVA/PVP blends filled with different filling levels of gelatin was slightly shifted towards temperatures lower than this of the pure PVA/PVP blend for samples X ≥ 40 wt%. The thermal properties of pure PVA/ of blend and their complexes were examined by DSC (Differential scanning calorimetry) to estimate how the thermal transitions of the prepared films were affected by the different concentrations of gelatin. In the case of PVA/PVP blend filled with chitosan system structural, optical, thermal and morphological studies were performed for pure PVA/PVP (50/50) blend and PVA/PVP blend filled with different concentrations of chitosan X (0.0, 5, 10, 20, 30, and 40 wt%) using casting method. The prepared films were investigated by different techniques. All techniques demonstrate the complexation between chitosan and the polymers blend. There were some changes in the IR absorption bands position and its intensities. UV-Vis analysis revealed intensity of the shoulder a round 273-280 nm increase with increasing chitosan content. Differential scanning calorimetry (DSC) showed thermal stability of the product samples and that has improved after filling chitosan increases. Scanning electron microscope (SEM) images of different concentrations of films revealed that large crystals characteristic of chitosan were also frequently present, when chitosan content increase upto 20 wt%, rough surfaces and crystalline structures are the dominant features. The X-Ray diffraction (XRD) showed that the incorporation of chitosan into the polymeric matrix causes decreasing in the crystallinity degree of the samples and this indicates the complexation between the filler and the polymers blend. Thermogravimetric analysis (TGA) is used to study the samples in the temperature range of 30 – 500 ºC. Figures show typical TGA thermograms of weight loss as a function of temperature for the present system.