Coupled thermomechanics of single-wall carbon nanotubes

The temperature-dependent transverse mechanical properties of single-walled nanotubes are studied using a molecular mechanics approach. The stretching and bond angle force constants describing the mechanical behavior of the sp2 bonds are resolved in the temperature range between 0 and 1600 K, allowing to identify a temperature dependence of the nanotubes wall thickness. We observe a decrease of the stiffness properties (axial and shear Young’s modulus) with increasing temperatures, and an augmentation of the transverse Poisson’s ratio, with magnitudes depending on the chirality of the nanotube. Our closed-form predictions compare well with existing molecular dynamics simulations.