Radiation Vulcanization of MDPE/EPDM Blends Loaded with White and Black Fillers:

Blends of 60/40 phr of MDPE/EPDM have been subjected to radiation vulcanization by gamma rays of 60Co in the presence of either HAF carbon black or white Hisil. The effect of the level of loading with Hisil has been followed up in the range of 0-100 phr. Mechanical properties, namely, elongation at break, tensile modulus and tensile strength were followed up as a function of irradiation dose for different loading of the blend with Hisil. The most appropriate degree of loading has been found to be 50-75 phr of Hisil. Comparison of mechanical properties of blends loaded with 50 phr of either HAF black or Hisil has been carried out. The data obtained indicated that Hisil is more effective as reinforcing filler than HAF black for radiation vulcanized MDPE/EPDM blends. The improvement attained in mechanical properties may be attributed to the reinforcing effect of filler as well as the induced cross-linking by radiation.