الفهرس 
INTRODUCTION AND LITERATURE SURVEYOnly 14 pages are availabe for public view
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Abstract
The present thesis consists of five main chapters as follows:
Chapter 1: Entitled ”Introduction and literature survey” Describes a general introduction to the subject and a brief review of the previously published scientific work in the area of interest.
Chapter 2: Entitled “Analytical Techniques and Theoretical concepts” Introduces the theoretical background of X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM),Field emission scanning electron microscope (FESEM), fourier transform infrared (FTIR) spectroscopy, ultraviolet-visible-near-IR (UV-Vis-NIR) spectroscopy measurements, dielectric spectroscopy and molecular modeling.
Chapter 3: Entitled “Materials and Methods” where the first part of this chapter explains the fabrication of CuO, ZnO, and the polymer nanocomposite films containing CuO and ZnO using the solution casting method.
The second part is concerned with describing the analytical techniques used during the preparation of the thesis, and a brief description of them, which are XRD, HRTEM, FESEM, FTIR spectroscopy, UV- VIS-NIR spectroscopy and electrical impedance
spectroscopy (EIS).
Chapter 4: Entitled “Results and Discussion” This chapter is divided into two parts: the first part is concerned with the experimental results of the prepared CuO, ZnO, and the polymer nanocomposites of PVVH and NPs under study. The first experimental part presents the results of characterization of the prepared NPs using FTIR and XRD. FE-SEM and HR-TEM were used for studying the morphology and the composition of the material. The optical properties were studied using UV-Vis spectroscopy to provide knowledge about the structural changes of the nanocomposite films. The changes in dielectric constant and dielectric loss are studied as a function of frequency. The second part presents molecular modeling calculations that were carried out to confirm the analytical results for the films.
Chapter 5: Conclusion
In this thesis, the solution casting method was utilized to synthesize nanocomposite films based on PVVH and different concentrations of CuO and ZnO NPs. The XRD diffraction patterns of PVVH loaded with different concentrations of CuO NPs reflect the amorphous nature of PVVH. The effect of CuO and ZnO nano filler insertion with PVVH bonding was demonstrated by changes in peaktroughs in the nanocomposite spectra. For FTIR assignment, PVVH doped with different concentrations of CuO and ZnO NPs showed that the band intensities are increased by increasing filler concentration. A new band appeared and its intensity increased with CuO and ZnO NPs. The absorption edge of the nanocomposites was red-shifted, indicating that the optical band gap of PVVH may be modified using small amounts of nano filler. The samples’ red shift in absorption edge
revealed hydrogen bonding between the nanofiller and the –OH groups or C=O group in PVVH polymer. Optical properties such as bandgap energy and Urbach energy indicated that the addition of CuO and ZnO NPs into PVVH polymer induced variations in the number of available final states as a function of composition ratio. Also, CuO and ZnO NPs changed the electronic structure PVVH by doping via deformationpotential, formation of localized band states, and Coulomb interaction. The shifting of the absorption edge, bandgap, Urbach energy, and variations of the optical bandgap could be important in optical communications, waveguide design, and optoelectronic device design. Addition of CuO-NPs to the PVVH polymer enhanced UV-blocking performance, it is noted that films doped with CuO NPs are less transparent than pure PVVH film. The results showed that PVVH/CuO nanocomposite film with a concentration of 0.005 wt% CuO-NPs effectively reduced UV radiation, as the blocking percentage in UVC ranges reached 91%. Molecular modeling was carried out to confirm the analytical results for the films using Density functional theory(DFT) to study the effect of CuO and ZnO addition on the electronic properties of PVVH. Total dipole moment (TDM), HOMO/LUMOenergy gap and molecular electrostatic potential (MESP) are incorporated to study the changes that occurred in the electronic properties of the studied structures. The results showed that TDM increased, HOMO/LUMO energy gap decreased, and electronegativity increased due to the interaction of PVVH with CuO and ZnO. Additionally, the results showed that the most probable interaction is that precedes through the carbonyl and hydroxyl groups of PVVH which confirms the experimental results.