الفهرس 
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Abstract
Summary
The present study focused on the synthesis and characterization of polyvinyl alcohol (10 wt%) /lead mono oxide with different PbO contents (0.8, 1, 1.2 and 1.5 g) films. The samples were prepared to perform a comprehensive analysis of the changes in the optical, structural, and nuclear radioactive attenuation properties. The prepared films were characterized by FT-IR spectra, EDX, Scan electron microscope (SEM), UV Spectra and Thermo gravimetric analysis (TGA).
The obtained results in this study can be summarized as follow:
A series of polyvinyl alcohol/lead mono oxide (PVA/PbO) films has been successfully prepared.
The function groups of the films were characterized by FT-IR spectra and the results showed that, in the FT-IR spectra of the blank PVA, O-H,C-H and C-O groups are clearly appear at 3400, 1450, and 1270 cm-1 respectively.
For (PVA/PbO) films, it is notice that, the absorption peaks in the region 1190–1075 cm-1 corresponding to C–O stretching of hydroxyl groups was found to be disappeared due to the interaction between the PVA polymeric matrix and PbO.
The surface morphology images examined by SEM of blank PVA and (PVA/PbO) films showed that the blank PVA film image is observed as homogenous and smooth surface. On the other hand, the images of (PVA/PbO) films have a grains of PbO distributed homogeneously on the surface of PVA film.
The presence of the PbO in the (PVA/PbO) films was determined by EDX analysis as supporting information confirming the presence of PbO in the PVA film. According to EDX analysis the existence of PbO in the PVA films was confirmed, while the EDX of the blank PVA showed the presence of C and O atoms only.
To illustrate the thermal stability of the samples over a wide range of temperature the thermo gravimetric analysis (TGA) were measured.
TGA and thermal degradation weight % of the blank PVA film and (PVA/PbO) at PbO contents 0.8 and 1.5 shows a multistage where the thermal decomposition increases by increasing the heating temperature. It can also be noticed that addition of PbO increases thermal stability up to 900oC where degraded weight % decreases from 96.19 to 63.55 and 54.45 for the blank PVA, (PVA/PbO) 0.8 and 1.5 g respectively.
A study of the optical properties, which showed a decrease in the optical band gap energy value of (PVA / PbO) films with increasing lead mono oxide contents.
The refractive index of PVA increases gradually with the increase in PbO concentration
Density and hardness are effective tools for examining the structure and the changes that occurred in the films.
PVA has lower values of density and hardness but after adding PbO to PVA, the density and hardness increase. The increase in density is due to the higher values of the molecular weight of PbO.
Hardness results showed higher hardness values for PbO-containing samples, and this may be due to shortening of the bonds, which leads to more bond strength.
By studying attenuation properties of gamma rays, it was found that these films increased attenuation of gamma rays by increasing the addition of PbO to PVA, and that the linear attenuation coefficient increased significantly with the increase in the thickness of the films as well.
Also, the mass attenuation coefficient, which depends on the density of the films, increases with the addition of PbO to PVA and decreases with the increase in the energy of gamma rays, which proves the possibility of using these films that contain a higher percentage of lead mono oxide as a protective shield from gamma rays with less thickness.