Simulation of dynamic mechanical and viscoelastic behavior in polymer/clay nanocomposites

摘要

Viscoelastic behavior of a polymer-based composite displays the energy storage and damping capabilities of the composite. Simulation and numerical modeling of viscoelastic behavior can aid to estimate the viscoelastic data and optimize the formulations of composites. It is possible to simulate the viscoelastic behavior of a polymeric composite by using the dynamic mechanical analysis (DMA) data of pure polymeric matrix and elastic properties of reinforcement. In this study, three-dimensional FE analysis was performed to study the viscoelastic behavior of poly(butylene terephthalate)(PBT)/polyurethane/clay nanocomposite by employing representative volumetric element and explicit dynamic analysis. A modified generalized Maxwell model was employed to express the viscoelastic behavior of polymer matrix. Experimental results of DMA for PBT/polyurethane and also elastic data of nanoclay were used in the finite element modeling, and subsequently, the storage and loss moduli of nanocomposite were predicted. The results of simulations were close to those of experiments particularly at low clay content (2 wt%). The aggregation of clays at higher content (4 wt%), increased the differences between experimental and FEM results.