Enhancement of flame retardancy and mechanical properties of HDPE/EPM based radiation shielding composites by electron beam irradiation

Radiation shielding materials based on polymer or its composites require higher material properties to endure the harsh radiation environments. In this investigation, electron beam (E-beam) irradiation and/or cross-linking agent triallyl cyanurate (TAC) were applied into the composites of a high density polyethylene (HDPE)/ethylene propylene monomer (EPM) blend containing B2O3 and/or PbO. The tensile strength increased as much as twice while the elongation enhanced more than 5 times by irradiation of 150 kGy with 10 MeV E-beam. Further enhancement of the tensile and elongation properties was achieved by applying both 1 wt.% TAC and E-beam irradiation, while use of 1 wt.% TAC alone decreased the mechanical properties. Flame retardancy of the polymer composites by mean of limit oxygen index (LOI) also achieved to higher than 21 without using any flame retardant additive.