Design and evaluation of multi-layer polybenzoxazine composites for enhanced gamma and neutron shielding

This study investigates the gamma and neutron shielding performance of novel polybenzoxazine (PBz) based composites reinforced with Mo2C, Boron, and WS2 additives. The additives are mixed into the matrix at various mass ratios and then each sample is evaluated in terms of radiation interactions. A three-layered shielding structure was further designed with PBz-Mo2C-25 as the front layer, PBz-B-25 as the intermediate layer, and PBz-WS2-25 as the rear layer. The obtained results show that multi-layer configuration, PBz-3L, further enhanced low-energy neutron attenuation, achieving substantially greater reductions in thermal and epithermal flux compared to single-layer Mo2C- and WS2-reinforced composites. For photons, the multilayer structure achieves radiation protection efficiency (RPE) values exceeding 99 % at low gamma energies. Total ionizing dose (TID) and displacement per atom (DPA) analyses are also reported. These findings confirm the superior shielding capability of the three-layer composite, highlighting its potential for advanced radiation protection applications in nuclear and aerospace environments.