Thermal and mechanical properties of blends of LDPE and EVA crosslinked by electron beam radiation

Low density polyethylene (LDPE) blends with different percentages of ethylene vinyl acetate (EVA) irradiated with 10 MeV electron beam in the range of 50-250 kGy at room temperature. The effect of irradiation and EVA content on the mechanical and thermal properties of LDPE was studied. It was revealed that for all blends increasing the applied dose up to 150 kGy would result in decrease in the specific heat capacity (c(p)) and thermal conductivity (k) of LDPE and then raised slightly with further increased in radiation doses. The gel content showed that under the irradiation, the crosslinking density at each irradiation dose depends almost on the amorphous portions of the LDPE/EVA. The mechanical properties of LDPE/EVA blends were found to be influenced by the electron beam irradiation and EVA content. It can be deduced that the mechanical properties of LDPE are improved by blending with EVA and irradiated by electron beam. Fourier transform infrared (FTIR) spectroscopy was used to characterize the structure of LDPE. Result indicates small variation in crystalline content, which could be increased or decreased on the formation of important bond groups.