Pull-out simulations of interfacial properties of amine functionalized multi-walled carbon nanotube epoxy composites

In this work the effect of amine functionalization of carbon nanotubes (CNTs) on the interfacial bonding characteristics between amine functionalized CNTs and LY556 resin has been investigated using molecular dynamics (MD) simulations. By analyzing the interfacial shear stress of nano composites (reinforced with single, double and triple walled CNTs), the effect of functionalization with Ethylene-di-amine (E-NH2) functional group has been examined. This study investigates the effect of functionalization with up to ten E-NH2 groups on the potential energy, pull-out energy and interfacial shear strength of different functionalized CNTs structures with reference to pristine CNTs. MD simulation proves that the interfacial bonding and shear stress between the CNTs and LY556 resin matrix depends on the degree of functionalization of CNTs. Thus optimum functionalization of CNT surface can be an effective way to improve the load transfer between the CNTs and resin. An artificial neural network based non-linear regression model is also developed for energy required to pullout different walled CNTs from the epoxy matrix. It has been observed that ANN modeling produced best results for MWCNT pullout as compared to SWCNT and DWCNT. This study will assist in the modeling, simulation and design of advanced nanotube reinforced polymer composites for potential real life applications, particularly in military structural applications.