Attenuation properties of poly methyl methacrylate reinforced with micro/nano ZrO2 as gamma-ray shields
Mahmoud T. Alabsy,
Mahmoud I. Abbas,
Alaa Y. El-khatib
et al.
Abstract:This research aimed to examine the radiation shielding properties of unique polymer composites for medical and non-medical applications. For this purpose, polymer composites, based on poly methyl methacrylate (PMMA) as a matrix, were prepared and reinforced with micro- and nanoparticles of ZrO2 fillers at a loading of 15%, 30%, and 45% by weight. Using the high purity germanium (HPGe) detector, the suggested polymer composites’ shielding characteristics were assessed for various radioactive sources. The experi… Show more
Rice straw is considered an agricultural waste harmful to the environment, which is abundant in most parts of the world. From this point, the present study is devoted to preparing new composites of two types of glue based on rice straw as a plentiful, low-cost matrix. Straw glue samples were prepared by mixing 20% wt. of rice straw with 80% wt. of animal glue (RS-An) and polyvinyl acetate (RS-PVAC) at different thicknesses of 1, 2, and 3 cm. The chemical composition of the prepared samples was identified by energy dispersive X-ray analysis and their morphology was examined using a scanning electron microscope. The mechanical test explored that RS-An and RS-PVAC respectively required a stress of 25.2 and 25.5 MPa before reaching the breaking point. γ-ray shielding performance was analyzed and determined at numerous photon energies from 0.059 to 1.408 MeV emitted from five-point γ-rays sources using NaI (Tl). Linear attenuation coefficient was calculated by obtaining the area under the peak of the energy spectrum observed from Genie 2000 software in the presence and absence of the sample. The experimental results of mass attenuation coefficient were compared with theoretical data of XCOM software with relative deviation ranging from 0.10 to 2.99%. Geant4 Monte Carlo simulation code was also employed to validate the experimental results. The relative deviation of XCOM and Geant4 outcomes was 0.09–1.77%, which indicates a good agreement between them. Other radiation shielding parameters such as half value layer (HVL), tenth value layer, and mean free path were calculated in three ways: experimentally, theoretically from the XCOM database, and by simulation using Geant4 code. Additionally, effective atomic number (Zeff), effective atomic number (Neff), equivalent atomic number (Zeq), and buildup factors were evaluated. It was confirmed that the γ-ray shielding properties were further boosted by mixing rice straw with the animal glue compared to the synthetic one.
Rice straw is considered an agricultural waste harmful to the environment, which is abundant in most parts of the world. From this point, the present study is devoted to preparing new composites of two types of glue based on rice straw as a plentiful, low-cost matrix. Straw glue samples were prepared by mixing 20% wt. of rice straw with 80% wt. of animal glue (RS-An) and polyvinyl acetate (RS-PVAC) at different thicknesses of 1, 2, and 3 cm. The chemical composition of the prepared samples was identified by energy dispersive X-ray analysis and their morphology was examined using a scanning electron microscope. The mechanical test explored that RS-An and RS-PVAC respectively required a stress of 25.2 and 25.5 MPa before reaching the breaking point. γ-ray shielding performance was analyzed and determined at numerous photon energies from 0.059 to 1.408 MeV emitted from five-point γ-rays sources using NaI (Tl). Linear attenuation coefficient was calculated by obtaining the area under the peak of the energy spectrum observed from Genie 2000 software in the presence and absence of the sample. The experimental results of mass attenuation coefficient were compared with theoretical data of XCOM software with relative deviation ranging from 0.10 to 2.99%. Geant4 Monte Carlo simulation code was also employed to validate the experimental results. The relative deviation of XCOM and Geant4 outcomes was 0.09–1.77%, which indicates a good agreement between them. Other radiation shielding parameters such as half value layer (HVL), tenth value layer, and mean free path were calculated in three ways: experimentally, theoretically from the XCOM database, and by simulation using Geant4 code. Additionally, effective atomic number (Zeff), effective atomic number (Neff), equivalent atomic number (Zeq), and buildup factors were evaluated. It was confirmed that the γ-ray shielding properties were further boosted by mixing rice straw with the animal glue compared to the synthetic one.
Paraffin composites with iron-encapsulated multi-walled carbon nanotubes (Fe@MWCNTs) (10 and 20 wt%) – lightweight, corrosion-resistant, and prone to shape change at the average room temperature with the warmth of hands.
Defects of high atomic materials gamma-ray shielding such as low chemical stability, low mechanical properties, and heaviness lead us to investigate other light and flexible materials such as polymers. Polymer-doped nanosized materials are the most frequently examined materials. In this study, polyethylene terephthalate [(C10H8O4)n] was doped with Ni0.5Zn0.5Fe2O4 nanoparticles up to 40 wt% (0.0, 10.0, 20.0, 40.0 wt%) prepared by Sol-Gel auto-combustion method with the help of Gelatin. The polyester/Nanofiller composite structures were identified using X-ray photoelectron spectroscopy, X-ray diffraction, Scanning, and Transmission electron microscope as well as density measurements. X-ray photoelectron spectroscopy confirmed the successful doping of nanofiller in the polyester structure as Zn signals appear in the atomic composition and Fe signals appear in the deconvolution of the peaks. X-ray diffraction, transmission, and scanning electron microscope display the same result. X-ray diffraction graph information with the Scherer equation offered the crystal size of the composite (26 nm). Polyester/nanofiller samples were scanned against gamma-ray and experimental shielding factors were computed using a narrow beam transmission technique with sodium iodide detector and two-point sources Cs-137 and Co-60. Experimental Linear and mass attenuation coefficient values swelled as percentages of nanofiller increased in the polyester structure. Experimental Mass attenuation values were compared with theoretical ones estimated from XCOM and Physics-X programs. The difference between them does not exceed 12% which is acceptable as the X-ray photoelectron spectroscopy atomic composition utilized in the theoretical data calculation does not reveal Ni signals. This may occur at the depth of the composite structure. Finally, the half-value layer, the Tenth value layer, and the Mean free path are determined experimentally, and their values are reduced as the nanofiller doping percentage rises in the structure. This result confirms the efficiency of nanofiller addition to the polyester structure to attenuate gamma-ray.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.