Enhancement of Friction between Carbon Nanotubes: An Efficient Strategy to Strengthen Fibers

TL;DR

This study demonstrates that applying pressure to carbon nanotube bundles induces collapse, significantly increasing intertube friction and strength, offering a promising method to enhance nanotube fiber performance at ambient conditions.

Contribution

The paper introduces a pressure-induced collapse method to enhance intertube friction and strength in carbon nanotube fibers, a novel approach for fiber reinforcement.

Findings

Intertube friction increases by 1.5 to 4 times after collapse.

Collapsed structures have significantly reduced cross-sectional area.

The method can produce fibers potentially stronger than carbon fibers.

Abstract

Interfacial friction plays a crucial role in the mechanical properties of carbon nanotube based fibers, composites, and devices. Here we use molecular dynamics simulation to investigate the pressure effect on the friction within carbon nanotube bundles. It reveals that the intertube frictional force can be increased by a factor of 1.5 ~ 4, depending on tube chirality and radius, when all tubes collapse above a critical pressure and when the bundle remains collapsed with unloading down to atmospheric pressure. Furthermore, the overall cross-sectional area also decreases significantly for the collapsed structure, making the bundle stronger. Our study suggests a new and efficient way to reinforce nanotube fibers, possibly stronger than carbon fibers, for usage at ambient conditions.