Molecular dynamics simulations of the influence of chemical cross-links on the elastic moduli of polymer-carbon nanotube composites

Abstract

In this article we compare the Young modulus of polyethylene carbon nanotube composites with chemical cross-links between the nanotube and the polyethylene matrix to the modulus of a composite with weak non-bonded matrix-nanotube interactions only. To this end, we employ molecular dynamics simulations using the Parrinello-Rahman approach, where all systems are modeled with a reactive many-body bond order potential due to Brenner. To analyze the effect of chemical cross-links on the Young modulus, we study systems where different amounts of carbon atoms of a capped (10,10) carbon nanotube have been cross-linked to a surrounding polyethylene matrix. Our results show that the Young modulus and thus the reinforcement of a composite material increases with the amount of cross-links.