Gamma Radiation Effects on the Mechanical Stability of Polyethylene Composites: Effects of Filler Dimension and Absorbed Dose

Incorporating multifunctional nanostructured materials that absorb radiation into polymers enhances their radiation-shielding properties. The role of boron nitride (BN) as an effective filler to enhance mechanical and shielding properties and resist irradiation has yet to be studied in detail. Our study examined the effects of gamma radiation doses ranging from 0 to 100 kGy on the mechanical properties of high-density polyethylene (HD) reinforced with two types of BN with different dimensions: hexagonal boron nitride (hBN) and boron nitride nanosheets (BNNSs). Scanning electron microscopy micrographs showed some aggregated plates with consistent distribution uniformly distributed in all regions in the matrix. This suggests proper adhesion between polyethylene and BN. The study showed that HD, 1 wt.% composite, and 1 wt.% nanocomposite samples experienced a 58%, 47%, and 33% reduction in elongation at break at 100 kGy compared to nonirradiated samples. The loss of tensile strength at 100 kGy for HD, 1 wt.% composite, and 1 wt.% nanocomposite was 57%, 44%, and 44%, respectively, compared to the nonirradiated samples. It is concluded that the addition of BNNSs in lower dimensions than hBN into polyethylene reduces the destructive effects of radiation. This is a way to improve the stability of polymer shields against ionizing radiation.