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Carbon‐based tubular materials have sparked a great interest in future electronics and optoelectronics device applications. In this work, we computationally studied the mechanical properties of nanotubes generated from popgraphene (PopNTs). Popgraphene is a 2D carbon allotrope composed of 5‐8‐5 rings. We carried out fully atomistic reactive (ReaxFF) molecular dynamics for PopNTs of different chiralities (()n,0 and ()0,n ) and/or diameters and at different temperatures (from 300 up to 1200 K). Results showed that the tubes are thermally stable (at least up to 1200 K). All tubes presented stress/strain curves with a quasi‐linear behavior followed by an abrupt drop of stress values. Interestingly, armchair‐like PopNTs (()0,n ) can stand a higher strain load before fracturing when contrasted to the zigzag‐like ones (()n,0 ). Moreover, it was obtained that Young's modulus (YMod) (750–900 GPa) and ultimate strength (σUS) (120–150 GPa) values are similar to the ones reported for conventional armchair and zigzag carbon nanotubes. YMod values obtained for PopNTs are not significantly temperature‐dependent. While the σUS values for the ()0,n showed a quasi‐linear dependence with the temperature, the ()n,0 exhibited no clear trends.

Popgraphene (PopG) is a new 2D planar carbon allotrope which is composed of 5–8–5 carbon rings. PopG is intrinsically metallic and possesses excellent thermal and mechanical stability. In this work, we report a detailed study of the thermal effects on the mechanical properties of PopG membranes using fully‐atomistic reactive (ReaxFF) molecular dynamics simulations. Our results showed that PopG presents very distinct fracture mechanisms depending on the temperature and direction of the applied stretching. The main fracture dynamics trends are temperature independent and exhibit an abrupt rupture followed by fast crack propagation. The reason for this anisotropy is due to the fact that y‐direction stretching leads to a deformation in the shape of the rings that cause the breaking of bonds in the pentagon‐octagon and pentagon‐pentagon ring connections, which is not observed for the x‐direction. PopG is less stiff than graphene membranes, but the Young's modulus value is only 15 % smaller.