Nonlinear viscoelastic effective behavior for composites at finite particle concentration

A micromechanical model was proposed to estimate overall nonlinear viscoelastic behavior for particulate polymer composites at finite particle concentration. The method was based on the generalized secant method, Laplace-Carson transformation technique and double-inclusions method. The stress and strain curves for glass-beads/HDPE composite were predicted, and they agree well with the experimental ones. The results also show that the proposed model predicts a significant stiffer response than the one based on Mori-Tanaka model at finite particle concentration. The proposed method was also compared with the homogenization model in a linear viscoelastic framework, the results show that GB/HDPE presents an important nonlinear viscoelastic behavior, the linear viscoelastic model fails to characterize its rate-dependent behavior.