Effect of Interface Modification on the Mechanical Behavior of Carbon Nanotube Reinforced Composites Using ParallelMolecular Dynamics Simulations

Molecular dynamics (MD) simulations play an important predictive role in understanding the behavior of nanoscale systems. In this paper, parallel MD simulations are used to understand the mechanical behavior of interfaces in CNT based composites. We present an algorithm for parallel implementation of MD simulations of carbon nanotube (CNT) based systems using reactive bond order potentials. We then use that algorithm to model the CNT-polymer interfaces with various levels of interaction as (a) described only by long range Van Der Waals interactions (b) chemically bonded with fixed matrix and (c) chemically bonded with matrix explicitly modeled. It is shown that interface strength based on non bonded interactions is very low (of the order of few MPa) and it can be significantly improved through surface chemical modification of CNTs (to an order of a few GPa). It is further noted that chemical bonding between functionalized nanotube and matrix during processing is essential to obtain good interface strength and hence a better composite. Keyword: Carbon nanotube composites, interfaces, parallel molecular dynamics.