Radiation shielding and enhanced thermal characteristics of high-density polyethylene reinforced with Al (OH)3/Pb2O3 for radioactive waste management

Abstract

The disposal of naturally occurring radioactive material (NORM) needs to be controlled and it is better to be packed in a suitable container to ensure acceptable levels of risk. High-density polyethylene (HDPE) can be used to produce composite materials as a good shielding material at minimal cost and lighter weight. In this study, different Al(OH)3 concentrations were incorporated in an HDPE matrix containing certain Pb2O3 concentrations through a hot compression molding process. The effect of Al(OH)3concentration, as well as the irradiation dose on the mechanical properties of the prepared composite, were investigated. Thermogravimetric analysis (TGA) was used to examine the thermal stability of the prepared composite whereas an X-ray diffractometer (XRD) confirmed the presence and homogeneity dispersion of the Al(OH)3 and Pb2O3 into the HDPE matrix. The radiation shielding capabilities of the prepared HDPE/Al(OH)3/Pb2O3 composite sheets were examined using 137Cs radioactive source with activity 5 μCi. The gamma-rays attenuation coefficient for the composite's sheets was measured as a function of Al(OH)3 percentage. The data shows that the tensile strength of the prepared composite sheets increases slightly with reinforcement materials and the elongation decreases whereas the exposure to gamma rays improves their tensile strength with an insignificant effect on the elongation. The sample containing an amount of 50% Al(OH)3 wt% has a good shielding characteristic and the Win XCOM program shows a good agreement between the calculated and WinX com attenuation coefficient values. The obtained results recommend the use of the prepared HDPE/Al(OH)3/Pb2O3 as a promising candidate material for the fabrication of a package with low-energy 137Cs radiation shielding capability.