International Journal of Radiation Research

en A Simulation and experimental study on neutron attenuation of polyester composites incorporated with boron carbide micro- and nano-particles Radiation Biology Radiation Biology تحقيق بديع Original Research <div style="text-align: justify;">Background: To mitigate neutron exposure hazards in industries like aerospace, flexible, lightweight polymer-based shields with high-temperature tolerance have been developed using suitable fillers that moderate fast neutrons and capture slow neutrons, ensuring reliable radiation protection. Material and Methods: This study involved exposing unsaturated polyester resin (UPS) composites reinforced with nano- and micro-sized boron carbide (B₄C) to neutron radiation from a ²³⁹Pu–Be source. Various weight percentages (0.5%, 1%, 2%, and 5%) of nano- and micro-B₄C fillers, along with thicknesses of 2.5 mm, 5 mm, 7.5 mm, and 10 mm, were evaluated. Experimental measurements were carried out to count fast and thermal neutrons, measure the macroscopic cross-section, half value layer, and Geant4 Monte Carlo simulations were performed for benchmarking. Results: Higher concentrations of B₄C resulted in increased total cross-section values and decreased half-value thickness measurements. At 5mm, 7.5mm, and 10 mm thicknesses, significant differences between nano- and micro-composites emerged at 2 wt.% (p < 0.05), becoming more pronounced with higher filler concentrations and greater sample thickness. These findings confirm the superior neutron attenuation performance of nano-sized B₄C, attributed to its higher surface-to-volume ratio and improved dispersion within the matrix. Geant4 simulations closely matched the experimental data at higher filler loadings, except under certain conditions. Conclusion: Both experimental and simulation results confirmed that protection improves with increased thickness and filler weight percentages, as expected. The study also highlighted the impact of nanotechnology on shielding properties, showing its advantage over micro-sized samples.</div> Neutrons, polyesters, boron carbide, nanoparticles, microparticles. 779 787 http://ijrr.com/browse.php?a_code=A-10-1-1577&slc_lang=en&sid=1 S. Sabokro 7900319475328460034393 7900319475328460034393 No Medical Physics and Engineering Department, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran J. Moradgholi 7900319475328460034394 7900319475328460034394 No Department of Materials Engineering, Isfahan University of Technology (IUT), Isfahan, Iran P. Rafiepour 7900319475328460034395 7900319475328460034395 No School of Engineering, Persian Gulf University, Mahini Ave, Bushehr 7516913817, Iran S.M.J. Mortazavi mortazavismj@gmail.com 7900319475328460034396 7900319475328460034396 Yes Medical Physics and Engineering Department, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran