The third criterion studied is the transverse strength of the layered models. The equilibrated models of the three polymer systems with a polymer mass fraction of approximately 0.4 were used for this evaluation. This polymer mass fraction is comparable with previously reported data . To assess the transverse tension behavior, the simulation box was subjected to a uniaxial strain in the direction perpendicular to the flCNT plane at a constant strain rate of 2×10 8 s -1 until there was total separation of one of the CNT/polymer interfaces or a maximum of 150% strain was reached. The overall system stresses and strains were recorded, and the corresponding stiffness, strength, and toughness values were calculated . An R script was used for this analysis. It is important to note that in these simulations, the upper and lower walls of single layers of flCNTs did not separate from each other, as the flCNT/polymer interface always failed first. Thus, the results are naturally focused only on the flCNT/polymer interface mechanical behavior.