Effect of silica filler on dynamic mechanical properties of lonic elastomer based on carboxylated nitrile rubber

Variation of dynamic mechanical propeties like storage modulus (E′) and loss tangent (tan δ) with temperature show the presence of two transitions in the carboxylated nitrile rubber (XNBR) molded in the presence of zinc oxide (ZnO). The low‐temperature transition is due to the glass–rubber transition (Tg) of XNBR, and the high‐temperature transition is due to formation of ionic clusters. Incorporation of reinforcing silica filler makes the high temperature transition more prominent and high filler loading casues a shift of the transition temperature to the higer side. It is believed that the rubber–filler interaction in the cluster region causes striking changes in the variation of E′ and tan δ with a double‐strain amplitude (DSA).