الفهرس 
Aim of the WorkOnly 14 pages are availabe for public view
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Abstract
The present thesis was concerned about studying physical properties of polyethylene oxide /sodium alginate (PEO/SA) polymer blends to obtain the optimum concentration suitable for the suggested application by studying some physical properties of the PEO/SA polymer blends prepared by casting technique. Structural, optical, thermal, mechanical and electrical properties of polymer blend have been studied using X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, Ultraviolet Visible (UV/Vis.), Differential scanning calorimetry (DSC), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), mechanical properties (stress–strain curve) and AC Conductivity. X-ray diffraction shows the amorphous nature of all prepared samples. It also shows a decrease in the crystalline region due to raising the doping level. Fourier Transform Infrared (FT-IR) spectra showed a change in intensities of some peaks after addition of MWCNTs, these changes were attributed to the interaction between PEO/SA blend and MWCNTs. UV/Vis. spectroscopic analysis indicated that an absorption band centered around 202 nm for PEO/SA film, which was attributed to п →п* transition, due to existence of double bond as shown in FT-IR measurement, this edge shifted towards longer wavelengths with increasing ratio of MWCNTs. These red shifts denote the complexation between the nanotubes and the polymeric matrix. Optical energy gap (Eg) decreased with increasing concentration of MWCNTs. Scanning electron microscopy exhibited a homogeneous growth mechanism and indicated the partial compatibility between the nanocomposite components. Differential scanning calorimetry (DSC) results was observed a single glass transition temperature (Tg) for blends this confirming existence miscibility within the blends. The causes for best thermal stability of some blends may be described by measurements of interactions between C=C groups of PEO and the α-hydrogen of SA or C=O, Cl–C interactions. The TEM micrographs showed MWCNTs consist of long tubes with hollow cores and many layers with diameter is range 13.30 - 22.16 nm. Mechanical analysis show that incorporation of MWCNTs improving the mechanical properties as both the tensile stress and elastic modulus of the nanocomposites increase with increasing filler concentration, which means that addition of MWCNTs can improve the mechanical properties of the composites. AC conductivity of PEO/SA blend was greatly improved for increase both MWCNTs concentration and temperature due to increment of charge carrier and it’s mobility. Both dielectric constant and dielectric loss were increased with decreasing frequency and increase with temperature. At high values of (f), the dielectric constant permittivity and dielectric loss reached a fixed values due to interfacial polarization. Based on the results obtained, it is believed that PEO/SA with MWCNTs may provide a new insight into their potential applications in energy storage systems as they are environmentally friendly and cost effective materials that modern industries require.