Effects of additives on the radiation resistance of heat-curable silicone rubber

Effects of five kinds of aromatic additives (biphenyl, naphthalene, phenanthrene, benzophenone and- diphenylacetylene) on radiation resistance of heat-curable silicone rubber were studied. The changes in average mo- lecular weight between crosslinks (Mc) and mechanical properties before and after γ-ray irradiation of 400 and 600kGy in vacuum were analyzed. Protection mechanisms of the aromatic additives are discussed. The results show that the aromatic additives, especially diphenylacetylene, can improve radiation resistance of silicone rubbers.