Atomistic investigation of the interfacial mechanical characteristics of carbon nanotube reinforced epoxy composite

In this work, we investigate the interfacial mechanical characteristics of carbon nanotube (CNT) reinforced epoxy composite using molecular dynamics (MD) simulations. The MD simulations were carried out by developing two pull-out models; namely, the displacement-load model and the velocity-load model. The second-generation force field polymer consistent force field (PCFF) - is used in the current MD simulations. The effects of various parameters, such as epoxy density, length and diameter of a CNT, the CNT-epoxy interfacial thickness, LJ cut-off distance and capping conditions of a CNT on the interfacial mechanical characteristics have also been investigated and discussed. The results from the present pull-out model, which are validated with earlier studies, reveal that (i) the interfacial shear strength (ISS) of the CNT-reinforced epoxy composite is improved with the increase in the epoxy density, (ii) the ISS of the CNT-reinforced epoxy composite decreases with the increase in the values of length and diameter of a CNT, and the thickness of CNT-epoxy matrix interface, (iii) the LJ cut-off distance has marginal effect on the ISS and the pull-out force of CNT, and (iv) incorporation of an end cap in the simulations results high initial pull-out peaks, which well correlate with the experimental findings. (C) 2015 Elsevier Ltd. All rights reserved.