The Effect of Particle Size of Polyvinyl Alcohol/Bentonite Clay Mixture on the Radiation Shielding: A Monte Carlo Study

Abstract

Due to the harmful effects of ionizing radiation, shielding has become a crucial topic for radiation protection. Finding effective, non-toxic and low-cost shielding materials is imperative in ensuring the safety of individuals exposed to ionizing radiation. Whether a material is effective in shielding against radiation depends on the linear attenuation coefficient. In this study, linear attenuation coefficients were calculated using the MCNPX code for energy values of 81 keV (Ba-133), 140 keV (Tc-99m), 662 keV (Cs-137), 1173 keV, and 1332 keV (Co-60) by incorporating Bentonite Clay (BC) nanoparticles and micro-sized particles as additives into a Polyvinyl Alcohol (PVA) matrix. BC particles with a density of 50% were added to the PVA matrix using LAT and U cards. Simulations were performed with a mono-energetic source emitting 107 particles and a narrow beam geometry, and the counts of particles with diameters of 50 nanometers and 50 micrometers were calculated using the F4 tally. When the results obtained from the simulation were compared, it was observed that as the diameters of the added particles decreased, their effectiveness in radiation shielding increased for each energy value. Among them, the 50 nm BC particles added at a rate of 50% in PVA showed the highest effect at 1332 keV, with a 9.5% increase compared to 50 µm BC particles.