Strain Rate Effects on the Mechanical Properties and Energy Absorption of Styrene-Butadiene Rubber

The effect of strain rate on the mechanical properties of rubbery polymers, particularly styrene-butadiene rubber (SBR), has been studied in this research. Uniaxial compression tests were conducted on SBR at a range of strain rates from 0.001 to 220 s-1. The stress-strain characteristics and the relationship between strain rate and mechanical properties were examined, followed by an analysis of the strain rate sensitivity. The experimental results indicate that the compressive mechanical responses of SBR exhibit nonlinear and strain rate-dependent behavior, with yield stress and flow stress increasing exponentially with the logarithmic increase of strain rates. The energy absorption capability of SBR was then studied by analyzing the absorbed energy per unit volume and specific absorption energy as a function of strain rate. Finally, a visco-hyperelastic constitutive model, comprising a nonlinear spring and a Maxwell element, was proposed to describe the mechanical behavior of SBR. The model predictions were found to be in good agreement with the experimental data. These findings can serve as a guide for the design and optimization of SBR structures against impact loading.