Evaluation of the Tensile Strength in Carbon Nanotube-Reinforced Nanocomposites Using the Expanded Takayanagi Model

In this study, we used the Takayanagi model expanded by Loos and Manas-Zloczower for the tensile modulus to assess the tensile strength of polymer/carbon nanotube nanocomposites (PCNTs). The new model assumes the strengthening and percolating efficiencies of the interphase between the polymer matrix and the nanoparticles. We evaluated the suggested model with the experimental data of two PCNTs and found that this model successfully calculated the average levels of the percolation threshold, interphase thickness (t), and interphase strength (sigma(iN)). The percolation threshold > 0.004, interphase volume fraction < 0.06, percentage of nanoparticles in the network < 0.015, and CNTs radius > 30 nm caused the lowest relative tensile strength, less than the strength of the polymer matrix. Among the studied variables, the t and sigma(iN) parameters most significantly affected the tensile strength of PCNTs; when t = 25 nm and sigma(iN) = 17 GPa, there was 1300% improvement in the strength of the PCNT. This model can be applied in future studies to accelerate the material design process.