Efficient, flexible and lead-free composite based on room temperature vulcanizing silicone rubber/W/Bi₂O₃ for gamma ray shielding application

The aim of this study is to prepare a non-toxic, light, flexible and low-cost radiation shielding material that protects against gamma ray (γ-ray). So, flexible and lead-free gamma-ray-shielding composites based on room temperature vulcanizing silicone rubber matrix with 37.5% weight of tungsten (W) and bismuth oxide (Bi₂O₃) as filler materials were prepared by using a simple and well-established open mould cast technique. The shielding properties of the composites [linear attenuation coefficient (µ), transmittance, half value layer (HVL) and tenth value layer (TVL)] have been evaluated using ¹⁵²Eu radioactive source in the energy range (122–964 keV). The prepared composites show high performance in gamma-ray-shielding in comparison with commercial composite (76% Pb). The sample that was treated with 18.75 wt% W + 18.75 wt% Bi₂O₃ shows the lowest values of HVL and TVL in high energy levels and is the best-attenuating shielding for γ-ray compared to the other investigated samples. Morphological observations showed that increasing of Bi₂O₃ in samples can prevent from the accumulation of fillers. For this reason, the tensile strength and elongation at break improved with increasing of Bi₂O₃ in composites.