Influence of Carbon Nanotube Defects on the Elastic Modulus of Nanocomposite: Multiscale Simulation

In the present study, atomistic-based continuum modeling of single-walled carbon nanotube (SWCNT)-reinforced composite had been performed to predict the effective modulus of the nanocomposite through multiscale modeling. SWCNT of armchair type (10,10) was modeled with a three-dimensional beam element to estimate equivalent axial Young's modulus using finite element analysis (FEA) for pristine and defective CNTs. The equivalent modulus of CNT with 5% vacancy defects has been reduced by 35.35% in comparison to the pristine CNTs. In addition, molecular dynamics (MD) simulations were conducted on standalone CNT for pristine and defective CNTs. Further, long and short CNT-reinforced nanocomposites were modeled through interphase FE modeling using Representative Volume Element (RVE) which is comprised of three phases, i.e., SWCNT, interphase, and matrix. Finally, the effects of CNT defects, interphase property, modulus ratio, height fraction, and volume fraction on the overall elastic response of the nanocomposite were demonstrated by statistical analysis. The analytical expressions of effective elastic modulus of both short and long CNT-based nanocomposites have been derived through regression analysis.