Polyethylene composite doped with cadmium and tungsten oxide for neutron-gamma multilayer shielding

Abstract

Radiation shielding is crucial to ensuring the safety of the people and the environment. Concrete and lead are common materials with great shielding properties against gamma and neutron radiation, yet they have drawbacks such as being harmful to human health, high cost, and seismic vulnerability. Therefore, the aim of this study is to develop polyethylene (PE)-based composites doped with cadmium (Cd) and tungsten oxide (WO3), to determine the neutron-gamma shielding properties of the composites, and to compare the radiation shielding performance of multilayer shielding of the composites and the base PE. The composites were fabricated using the melt-mixing and hot-pressing methods. They were characterized using X-ray diffraction, micro-computed tomography scanning, and field emission scanning electron microscopy to observe the dispersion of filler particles in the PE matrix. Results show that the filler elements have good distribution in the composite. Their shielding performance was evaluated using the 241Am/Be neutron and 137Cs gamma sources at the Malaysian Nuclear Agency. The results show that the PE+20% WO3 has the highest values of neutron removal macroscopic cross-section and gamma linear attenuation coefficient for single-layer shielding. For multilayer configuration, PE+10%Cd with PE+10% WO3 (Cd10/W10) has the best mixed neutron-gamma radiation attenuation performance. The results will help in the development of alternative materials for better radiation protection.