Work

Flexible lead-free gamma-ray radiation shielding using La(OH)3-enhanced natural rubber composites

Year: 2025

Type: article

Abstract: Ionizing radiation is widely applied in medicine, industry, and agriculture, but it poses health risks for workers. Lead is effective for shielding, but is toxic and environmentally harmful. This study aimed to develop lead-free, flexible gamma-ray shielding composites by incorporating lanthanum hydroxide [La(OH)3] into natural rubber (NR). Composites with varying La(OH)3 contents (0–250 phr) were prepared using an open two-roll mill and compression molding. Microstructure, mechanical properties, and gamma attenuation were characterized, and results were compared with XCOM simulations. Gamma shielding was tested at 81–1332 keV using Ba-133, Cs-137, and Co-60 sources. SEM/EDS confirmed uniform La(OH)3 dispersion in the NR matrix. Density increased from 0.975 g/cm3 (NR) to 2.156 g/cm3 (La250/NR), and hardness rose from 27% to 53%. Tensile strength decreased from 13.1 MPa to 5.8 MPa, while elongation at break declined from 440% to 320%. At 81 keV, the mass attenuation coefficient increased from 0.161 to 2.029 cm2/g, and the half-value layer was reduced from 4.41 cm to 0.16 cm (~96% reduction). Experimental results agreed with XCOM within 20%. These findings highlight La(OH)3–NR composites as lightweight, flexible, and non-toxic alternatives for gamma radiation shielding.

Source: Journal of Radiation Research and Applied Sciences

DOI: 10.1016/j.jrras.2025.102150