الفهرس 
Theoretical Background and Literature ReviewOnly 14 pages are availabe for public view
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Abstract
In recent years, numerous novel materials have been developed and tested for radiation shielding purposes in order to protect individuals from the damaging effects of exposure emitted by radioactive nuclides and sources. For these purposes composite materials consist of the polymer polymethyl methacrylate PMMA, and nanoparticles of barium titanate (BaTiO3) for radiation shielding have been prepared and six samples with different concentration of BaTiO3 have been studied. XRD, FTIR, SEM, and UV/Vis spectroscopy were used to characterize the PMMA/BaTiO3 nanocomposite samples.
The results obtained may be summarized as follow:
The sonicated solution-casting method was used to successfully create the nanocomposite that was under examination. The examination using X-ray diffraction (XRD) demonstrates a change in the intensity of the highest peak situated at 2Ɵ = 31.62˚. This variation in peak intensity indicates the presence of BaTiO3 inside the PMMA matrix. This is shown by the linear rise in peak intensity that was observed as a function of filler content. According to the results of the FTIR research, the BaTiO3 nanoparticles and the PMMA polymer matrix have favorable dispersion and miscibility characteristics. This is shown by the fact that there was no FTIR band shift and there was a reduction in intensity. Scanning electron microscopy (SEM) pictures of pure PMMA and doped with different concentrations of barium titanate BaTiO3 nanoparticles suggest that the samples display a high degree of homogeneity. This is shown by the fact that the nanoparticles are evenly distributed throughout the matrix. The findings of X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR) provide further evidence that these hybrid nanocomposites were successfully formed. An indication of the successful development of these hybrid nanocomposites is the homogeneity of the distributed nanoparticles on the film surfaces. Optical characterization of the PMMA/BaTiO3 nanocomposite samples was carried out using UV/Vis spectroscopy. According to the findings of the research, the PMMA sample in its unadulterated form demonstrated transmittance values ranging from 80% to 90% throughout the majority of the wavelength ranges that were investigated. On the other hand, the transmittance levels of the nanocomposite films were roughly 40%, and this value was dependent on the ratio of inserted nanoparticles, which could be up to 10% by weight of BaTiO3. With a rise in BaTiO3 concentration, the optical bandgap of the films, both direct and indirect , display a reduction; nevertheless, the predicted values of refractive index increase. It was discovered that adding 10 wt% of BaTiO3 to a PMMA polymer resulted in the ideal concentration for gamma rays at all energy lines. as a result of its relatively low half-value layer (HVL) values for the studied range of gamma energy. This phenomenon also applies to MFP in its own unique way. It has been determined that the best concentration of BaTiO3 for attenuating all neutron energy is 15 wt. (%) of the material. As a result of the smallest mean free path (MFP) values it has, it demonstrates the lowest amount of attenuation. Nanocomposites made of PMMA and BaTiO3 have been shown to be effective shielding materials against gamma and neutron radiation; the suggested percentages of these two components, however, vary depending on the application.