Effect of gamma irradiation on the mechanical and dielectric properties of XLPE/TiO₂ nanocomposites

Polyethylene (PE) is widely used in power cables, but its performance limits its use in high-voltage applications. This study investigates the effect of gamma irradiation (20–100 kGy) on low-density polyethylene (LDPE) nanocomposites containing titanium dioxide (TiO₂) at 0, 0.5, and 2 phr and ethylene–vinyl acetate (EVA) at 0, 1, and 5 phr. Based on the results, X5 (LDPE/TiO₂-0.5) achieved the highest crosslinking efficiency at 100 kGy, while X16 (LDPE/TiO₂-2/EVA-5) exhibited superior tensile strength at 80–100 kGy. Dielectric permittivity decreased with increasing irradiation dose, particularly at 100 kGy, and breakdown strength peaked at 60–80 kGy. These findings provide insight into optimizing irradiation conditions for XLPE-based high-voltage insulation materials.