Evaluation of Elastic Properties of CNT/GNP/Epoxy Hybrid Nanocomposite for Different Weight Fractions of CNT and GNP

The present study aims to evaluate the elastic parameters of graphene nanoplatelet (GNP) and carbon nanotube (CNT) reinforced epoxy matrix hybrid nanocomposite (HNC) for different weight percentages of CNT and GNP. Combined weight percentages (wt%) of CNT and GNP have been separately considered as 1 wt% and 2 wt%, with mixing ratios between 0.11 and 9. Modified Halpin–Tsai (H–T) and rule of hybrid mixtures (RoHM) have been considered to evaluate elastic modulus of the HNC. Elastic modulus calculated using these two micromechanical models has been compared with experimental results reported in literature, and it was observed that the RoHM model shows better agreement with the experimental data with an average deviation of 18.02%. It was further revealed that elastic modulus decreased as the wt% of CNT increased within the mixing ratio of CNT and GNP. For both the wt% of reinforcements in the epoxy matrix, the optimal elastic modulus was evaluated for the mixing ratio equal to 0.11. The Young’s moduli of HNC are increased by 158.09% and 317.23% as compared to neat epoxy, respectively for 1 and 2 combined wt% of CNT and GNP, and considering a constant mixing ratio of CNT and GNP as 0.11. The rule of mixture model has been used to estimate Poisson’s ratio of CNT/GNP/epoxy HNC. It was observed that the Poisson’s ratio reduced with decrease in the wt% of GNP within mixing ratio.