On the elasto-plastic behavior of CNT-polymer nanocomposites

In this paper, a combination of molecular structural mechanics and micromechanics is employed to predict the elasto-plastic behavior of polymeric nanocomposites (NCs). Considering the CNT and its surrounding interface as a transversely isotropic equivalent fiber, we first develop a multiscale FEM-based method to obtain the corresponding elastic constants. Due to the perfect bond assumption between the equivalent fiber and the matrix, the obtained elastic constants are then implemented in Mori-Tanaka method to predict the stiffness and stress-strain behavior of the NC. 3D and 2D random distribution of nanofillers are explored. It can be perceived that 3D distribution leads to a more realistic prediction in comparison with the 2D one. However, at low volume fractions of CNT, their difference is not noticeable. The result of the proposed approach is compared with experimental work. Finally, based on the proposed method, an acceptable approximation for the ultimate strength of the NC is predicted.