Effects of PP/EPDM Blends Irradiated by γ-Rays

Improvement of the impact properties of PP can be achieved by the dispersion of elastomers in the PP matrix. In the field of PP/EPDM blends, most studies have been performed on improving the mechanical properties via dynamically vulcanized blends. The present work reports the results of irradiating PP and EPDM, a large decrease in melt flow rate is observed for PP, EPDM is easily crosslinked by γ-rays in air at room temperature. At low dose range radiation crosslinking of EPDM is enhanced due to the addition of TAIC. The radiation crosslinked EPDM containing 68% gel was obtained with the addition of 2% TAIC by 20kGy dose. From the above, radiation crosslinking of polymer blends containing PP and EPDM was studied. The impact of PP with 50% EPDM is increased by γ-irradiation from 1. 95kJ/m2 to 30 kJ/m2 in 20 kGy dose, the Vicat softening temperature is also increased from 85. 9℃ to 97℃. In this case, both crosslinking of EPDM phase and chain scission of PP phase played an important role, causing a more complex mechanical behavior.