A finite element study on the mechanical properties of polymer/hybrid nanocomposites

In the present work, the elastic modulus of two series of polymer/hybrid nanocomposites, with a combination of graphene oxide (GO) either with multi walled carbon nanotubes (MWCNTs) or carbon nanofibers (CNFs) at an equal ratio and varying the total loading, was studied by a 3D finite element method. The two polymers employed as matrices were linear low-density polyethylene (mLLDPE) and poly-lactic acid (PLA) and comparison with the experimental data has been performed. The different degree of the mechanical enhancement between the two series of the polymer nanocomposites at comparable nanofiller loadings was analyzed. Given the importance of the geometrical features, the assumptions of straight and curved CNTs/CNFs, agglomeration and a combination of agglomeration and curvature, four representative volume elements (RVEs) were generated within the frame of Digimat-FE. A closer approximation to the experimental data was achieved under the assumption of both agglomeration and curvature. The lowest deviation was detected for the PLA/GO/CNF hybrid nanocomposites at the three nanofiller loadings. It was revealed that considering the coexistence of agglomerates formation and the curvature of CNTs/CNFs is an important condition for predicting the Young’s modulus.