Enhancement of flame retardancy and radiation shielding properties of ethylene vinyl acetate based radiation shielding composites by EB irradiation

Abstract

Flame-retardant radiation shielding composites were processed using EVA matrix with magnesium hydroxide (Mg(OH)2), zinc borate (ZB) and bismuth oxide as filler materials. As filler content increased, the elongation at break and tensile strength of the materials decreased. Oxygen index (OI) of composites was higher than 27.2% when ZB content exceed 14 wt%. μm of materials gradually increased with the increase of bismuth oxide when tested by 137Cs. On the contrary, μm of materials decreased with the increase of bismuth oxide when tested by 60Co. Neutron shielding ratio of samples gradually increased with the increase of ZB when tested by Am-Be neutron source. Sample E with good comprehensive performances was selected and then modified by high energy EB irradiation. The mechanical properties, flame retardancy, and radiation shielding performances of modified composites were higher than those of the ordinary composites with the same filler mass fraction after being modified by electron beam irradiation with a dose of 175 kGy.