Polymers are often used in medical applications, therefore, some novel polymers and their interactions with photons have been studied. The gamma-ray shielding parameters for Polymethylpentene (PMP), Polybutylene terephthalate (PBT), Polyoxymethylene (POM), Polyvinylidenefluoride (PVDF), and Polychlorotrifluoroethylene (PCTFE) polymers were determined using the Geant4 simulation and discussed in the current work. The mass attenuation coefficients (μ/ρ) were simulated at low and high energies between 0.059 and 1.408 MeV using different radionuclides. The accuracy of the Geant4 simulated results were checked with the XCOM software. The two different methods had good agreement with each other. Exposure buildup factor (EBF) was calculated and discussed in terms of polymers under study and photon energy. Effective atomic number (Z_eff) and electron density (N_eff) were calculated and analyzed at different energies. Additionally, the half-value layer (HVL) of the polymers was evaluated, and the results of this parameter showed that PCTFE had the highest probability of interaction with gamma photons compared to those of the other tested polymers.

In this work, the γ -ray shielding characteristics of fabricated recycled polyvinyl chloride (rPVC) loaded with micro and nano fillers of PbO and CuO composites were investigated. The PbO/rPVC and CuO/rPVC composites were prepared by changing the percentage of injected materials (PbO and CuO) between 10% and 40% with additions by 10%. Gamma-ray attenuation properties, such as mass attenuation coefficients, linear attenuation coefficients and half-value layer for PbO and CuO-supported polymers were obtained in the energy range between 59.5 and 1408.0 keV using narrow beam transmission geometry. These experiments were carried out by using a HPGe detector and five standard radioactive sources [ ²⁴¹ Am, ¹³³ Ba, ¹³⁷ Cs, ⁶⁰ Co and ¹⁵² Eu]. Moreover, equivalent atomic numbers and the exposure buildup factor (EBF) values for incident photon energy in the range from 0.015 MeV to 15 MeV were also calculated by Geometric Progression (G-P) method. The experimental results revealed that, the measured values of the linear attenuation coefficients of the PbO/rPVC and CuO/rPVC composites showed their dependence on the type and the concentration of the filler (either PbO or CuO) and also on the incident gamma ray energy. Increasing the filler weight fractions wt.% in the rPVC matrix, increases the linear attenuation coefficients of the composite and the improvement is more significant in case of PbO compared to CuO of the same filler wt.% at the same energy. The results also demonstrated an enhancement in the radiation protection behavior of rPVC composites due to the addition of PbO and CuO fillers as nano-sized particles.

Polymer composites of polyvinyl chloride, PVC, were loaded up with micro and nano PbO/CuO particles. The added percentage of each by mass was 10 wt.%, 20 wt.%, 30 wt.%, and 40 wt.%, plus 40 wt.% of mixed composite (20 wt.% CuO + 20 wt.% PbO). The mass and linear attenuation coefficients of the investigated composites were measured as a function of gamma-ray energies going from 59.53 keV to 1408.01 keV utilizing standard radioactive point sources. To confirm the validity of these results the attenuation coefficients for bulk composites (PVC + PbO and PVC + CuO) were calculated by using the XCOM software. The results were in good agreement with the values obtained from the experimental work. By comparing the attenuation coefficients of the different composites it was found that those loaded with either nano PbO or CuO have higher values than those loaded with bulk sizes with the same percentage. Also, samples loaded with nano PbO have the highest attenuation coefficients even by comparing them with (20 wt.% CuO + 20 wt.% PbO), especially in the energy region below 1 MeV, but for greater energies, the values become very closed. The investigation of the mechanical properties of such composites due to the injection of bulk and nano metals reveals that tensile strength and Young's modulus of PVC nanocomposite sheets were notably increased with the increasing concentration of CuO and PbO nanoparticles. The CuO nanocomposite showed the highest values of flexural strength, toughness, and tensile strength among all the fabricated nanocomposite sheets.

In the current study, the gamma-radiation-shielding characteristics of novel gypsum–lime–waste marble-based mortars reinforced with micro-PbO and nano-PbO powders were investigated. In total, seven mortar groups, including a control mortar (named GLM), were prepared. The other groups contained10, 20, and 30 wt.% of both micro-PbO and nano-PbO as a waste marble replacement. This study aimed to explore the effect of particle size and concentrations of PbO powders on the γ-ray-shielding capability of GLM mortars. For this purpose, an HPGe detector and five standard radioactive point sources (²⁴¹Am, ¹³³Ba, ¹³⁷Cs, ⁶⁰Co, and ¹⁵²Eu) were employed to measure different shielding parameters, including the linear attenuation coefficient (μ), mass attenuation coefficient (μ_m), mean free path (MFP), half-value layer (HVL), and tenth-value layer (TVL), for the prepared samples in the energy range between 59.53 keV to 1408.01 keV. On the basis of μ_m values, other significant shielding parameters such as effective atomic number (Z_eff), effective electron density (N_eff), equivalent atomic number (Z_eq), and exposure buildup factor (EBF) were also computed to explore the potential usage of the proposed mortars as radiation protective materials. The results reported that the smallest HVL, TVL, and MPF, as well as the largest attenuation values, were obtained for mortars reinforced by nano-PbO compared to those containing micro-PbO. It can be concluded from the results that the mortar samples containing nano-PbO had a remarkably improved gamma-radiation-shielding ability. Thus, these mortars can be used for radiation shielding on walls in nuclear facilities to reduce the transmitted radiation dose.

This study aims to explore the radiation protection properties of white mortars based on white cement as a binder and Bi₂O₃ micro and nanoparticles in proportions of 15 and 30% by weight as replacement sand. The average particle size of micro- and nano-Bi₂O₃ was measured using a transmission electron microscope (TEM). The cross-sectional morphology and distribution of Bi₂O3 within the samples can be obtained by scanning electron microscopy (SEM), showing that nanoscale Bi₂O₃ particles have a more homogeneous distribution within the samples than microscale Bi₂O₃ particles. The shielding parameters of the proposed mortars were measured using the HPGe detector at various γ-ray energies emitted by standard radioactive point sources ²⁴¹Am, ¹³³Ba, ⁶⁰Co, ¹³⁷Cs, and ¹⁵²Eu. The experimental values of the prepared mortars’ mass attenuation coefficients (MAC) match well with those determined theoretically from the XCOM database. Other shielding parameters, including half value layer (HVL), tenth value layer (TVL), mean free path (MFP), effective electron density (N_eff), effective atomic number (Z_eff), equivalent atomic number (Z_eq), and exposure buildup factor (EBF), were also determined at different photon energies to provide more shielding information about the penetration of gamma radiation into the selected mortars. The obtained results indicated that the sample containing 30% by weight of nano Bi₂O₃ has the largest attenuation coefficient value. Furthermore, the results show that the sample with a high concentration of Bi₂O₃ has the highest equivalent atomic numbers and the lowest HVL, TVL, MFP, and EBF values. Finally, it can be concluded that Bi₂O₃ nanoparticles have higher efficiency and protection compared to microparticles, especially at lower gamma-ray energies.