Synergistic impact of ionic liquid on interfacial interaction and viscoelastic behaviors of silica filled nitrile butadiene rubber nanocomposites

Ionic liquid (IL) 1-ethyl-3-methylimidazolium acetate is used to explore the interactions between silica and rubber and replacement of silane for preparing volatile organic compounds-free vulcanizate nanocomposites. Herein we investigate the synergistic impact of IL on microscopic structure, nonlinear rheology and Mullins effect of silica filled nitrile butadiene rubber (NBR) nanocomposites. The results show that IL reacts with NBR chains and silica during compounding and vulcanization, which improves silica dispersion, bound rubber content and NBR crosslinking density and thus mediates the reinforcement and strain softening behaviors. In comparison with 5 phr usually used coupling agent bis(3-triethoxysilylpropyl)tetrasulfide, IL at the same amount could significantly improve tensile strength without influencing the dissipation energy of vulcanizates experiencing cyclic tensile deformation, which is enlightening for designing and producing vulcanizate nanocomposites with tailorable elasticity and dissipation behaviors.