Green Bi2O3–bentonite hybrid fillers for high-performance radiation-shielding polymer composites

In this work, different amounts of bentonite and Bi 2 O 3 NPs (ranging from 5 to 20 wt%) were used together in the fabrication of unsaturated polyester nanocomposites. These composites were evaluated as shielding materials at different energies using different gamma ray sources (Am-241, Cs-137, and Co-60). The results showed that as the filler percent increases, the density of composites and LAC values increase, where the UP-10B20B sample (which contains 10% Bi 2 O 3 NPs and 20% bentonite) has the highest LAC values. On the other hand, the results showed an increase of compressive strength values with addition of bentonite. In addition, the results indicated that UP-5B5B sample (which contains 5% Bi 2 O 3 NPs and 5% bentonite) has the highest compressive strength, and it decreases with increasing filler percentage. Also, thermal gravimetric analysis indicated that the nanocomposite sample has higher resistance to thermal degradation compared to pure UP. • New polyester composites-based nanomaterials were prepared. • The composites contain different ratios of Bi 2 O 3 NPs and bentonite. • The radiation shielding parameters were determined experimentally at different energies. • The highest concentration of Bi 2 O 3 NPs gives highest attenuation. • The addition of bentonite improves compressive strength of composites.