A theoretical study on the behaviour of strain conductivity in carbon nanotube/high-density polyethylene composites

Theoretical analysis of electron transport behaviour in carbon nanotube/high-density polyethylene (CNT/HDPE) composites successfully predict the strain conduction behaviour in CNT/HDPE nanocomposites. The conductivity below the percolation threshold can well be explained by the tunnelling conduction mechanism which can be explained as follows: The potential field within the connection is determined by the effective potential of the ideal polymeric solid. Certain assumptions have been made, such as treating the electrons in CNT sheets as free particles. As a result, the potential within the CNT sheets is close to zero. Additionally, the polyethylene (PE) insulating layer in the CNT-PE-CNT junction is assumed to act as a rectangular potential barrier in one- dimensional electrical fields along the x-axis. This resulted in finding a direct correlation between strain and the separation distance of the carbon nanotubes (CNTs). As the strain level rises, the gap between the CNTs widens, eventually reaching a critical threshold where they become no longer conductive. (author)