A Multi-scale Framework for the Prediction of the Elastic Properties of Nanocomposites

Nano-scaled matrix additives have found extensive use in industrial and engineering applications owing to their superior mechanical properties compared to their parent polymers. Despite the large number of numerical studies conducted on the mechanical properties of nanocomposites, the exact mechanisms of increased mechanical properties are still enigmatic. In this chapter, a hierarchical multi-scale approach for the prediction of the elastic properties of a boehmite/epoxy nanocomposite is developed. Starting on the atomistic level, the elastic properties of the constituents of the nanocomposite, namely the bulk polymer, the nanoparticle, and the interphase, are characterized. Coarse-grained simulations are then introduced, which enable modeling across a wide range of time and length scales compared with all-atom molecular dynamics simulations. Finally, the homogenized results from the nano-scale are eventually sequentially transferred to the micro-scale. The influence of the interphase, the agglomeration and the agglomerate size distribution on the elastic properties of the nanocomposite is also investigated in this chapter. A possible extension would be the prediction of elastic properties using CG simulations of nanocomposite unit cells to calibrate the continuum models.