High strain-rate and quasi-static mechanical characteristics of the natural rubber-based elastomer nanocomposite reinforced with alumina nanoparticles

The present study is devoted to investigating the mechanical characteristics of a novel natural rubber (NR)-based elastomer nanocomposite reinforced with carbon black and alumina nanoparticles acting as partial and primary reinforcements, respectively. Before conducting various mechanical tests on the specimens, the vulcanization properties of this elastomer nanocomposite was surveyed. It is demonstrated that adding the alumina nanoparticles to the NR-based elastomer matrix can significantly reduce the cure time and improve the quality of the vulcanizates. Then, the influence of alumina nanoparticles on the modulus, tensile strength, elongation at break, and energy absorption capacity of the elastomer nanocomposite were assessed, and the ideal nanoparticles’ weight percentage was determined to be 10%. This is supported by calculating the Reinforcing Efficiency Parameter (REP), indicating that the elastomer nanocomposite with 10% alumina has the best reinforcing efficiency in tensile properties. Also, using the Split Hopkinson Pressure Bar (SHPB), it was found that the material is exceptionally strain-rate sensitive, and the specimens exhibited much higher values of stiffness and energy absorption under high strain-rate loading. It is inferred from the results that the elastomer nanocomposite reinforced with the optimal amount of alumina nanoparticles can be an excellent candidate for energy absorption applications under high strain-rate loadings.