Molecular dynamics predictions of thermo-mechanical properties of carbon nanotube/polymeric composites

Abstract

In this study, the mechanical and thermal properties of carbon nanotube-reinforced polymeric nano-composite have been predicted by simulating molecular dynamics (MD). The polymer matrix is of epoxy polymer type with EPON828 resin along with EpiCure Curing Agent-3234 hardener which is reinforced with a single-walled carbon nanotube (SWCNT). Mechanical and thermal properties such as density, elastic modulus, Poisson’s ratio, and coefficient of thermal expansion (CTE) for various states, including the cross-linking degree of resin and hardener molecules 10–65%, carbon nanotubes (CNTs) with different diameters, and weight fraction of carbon nanotubes of 0.5, 1 and 2% have been estimated. The cell’s stiffness matrix in all cases was extracted, and thermo-mechanical properties were obtained using it. The placement of carbon nanotubes in a representative cell is completely random which has a random orientation, and the cell is dynamically analyzed separately under constant temperature and constant pressure conditions at the specified time, and after equilibration, its properties are extracted. The results show an obvious increase in the elastic modulus by increasing cross-linking degrees and an increase in the elastic modulus, and a significant decrease in the nano-composite CTE when the weight fraction of CNTs has increased. The experimental studies and simulation of other researchers were examined to validate the simulation that, the results are in good agreement with each other.