Rubber-based nanocomposites have become a research focus in the nuclear industry due to their wide application in wearable radiation protection devices.

This study aims to explore the γ-ray shielding mechanism of composite material of Bi₂WO₆ nanoparticles and natural rubber (NR), so as to provide theoretical support for the further materials preparation of low toxicity, light weight and high efficiency radiation shielding.

Bismuth tungstate (Bi₂WO₆) nanoparticles synthesized via hydrothermal process, additionally, WO₃ and Bi₂O₃ particles were prepared by ball milling method. Then, these particles were filled into natural rubber (NR) at the mass fraction of 30% to fabricate three composites: NR/Bi₂WO₆, NR/WO₃ and NR/Bi₂O₃. Finally, laser particle size analyzer, X-ray diffraction analysis (XRD) and field emission scanning electron microscope (FE-SEM), etc., were employed to access the mechanical properties of NR/Bi₂WO₆, and the γ-ray shielding effect was evaluated on the basis of the γ-ray shielding effects of Bi₂WO₆, WO₃ and Bi₂O₃.

The results show that the NR/Bi₂WO₆ nanocomposites achieves a γ-ray shielding factor of 13.6% for 59.5 keV (²⁴¹Am point source), which is significantly higher than NR/WO₃ (7.4%) and NR/Bi₂O₃ (9.2%). Furthermore, a comparison of WO₃ and Bi₂O₃ indicates that the interlayer effect of the Bi₂O₂²⁺ and WO₄^2- layers in the Bi₂WO₆ cell is conducive to increasing the probability of collisions between γ photons and extranuclear electrons.

The γ-ray shielding performance of NR/Bi₂WO₆ composites is significantly improved by the boundary complementary effect of both K and L layer absorption edges of W and Bi elements existed in Bi₂WO₆ nanoparticles, which enhances the attenuation efficiency of NR/Bi₂WO₆ to the γ-ray.