“Energy dissipation of elastomer nanocomposites at large strains and high strain-rates.”

Characterization of the mechanical behavior of rubbery materials at high strain rates is a nontrivial challenge. Many of the physical properties of rubbers are strain-rate dependent and therefore necessitates the understanding of the high-strain rate response of rubbery materials. Current methods to characterize the mechanical properties of rubbers typical probe the material response under low strain-rate, quasi-static conditions or dynamic conditions at low strain. A highly strained rubber undergoes free retraction when the material is suddenly released from one end. The resulting speed of the retracting material can be very fast, approaching the speed of sound in the material, and is related to the material’s molecular structure, modulus and internal friction. In this work, large strain, high strain-rate mechanical response of elastomer and elastomer-matrix nanocomposite materials are investigated by free retraction of highly-stretched samples. High-speed videos of rubber retraction are acquired and analyzed to characterize the mechanical properties of these materials at high strain rate, large strains. Furthermore, the role of filler-matrix interactions in elastomer nanocomposites in minimizing viscoelastic energy losses at large strain and high strain-rates are considered