Effect of carbon nanotube length on thermal conductivity of SWNT/PVA composites

In polymer nanocomposites, the enhancement efficiency of single-walled carbon nanotubes (SWNTs) on the thermal conductivity of polymers is primarily influenced by the length of the SWNTs. This study analyzes the thermodynamic properties of carbon nanotube/polyvinyl alcohol (SWNT/PVA) composites and investigates the impact of varying SWNT lengths on the thermal conductivity of the composite system through the application of the reverse non-equilibrium molecular dynamics simulation method (RNEMD). The simulation results reveal that the interaction energy between SWNTs and PVA is markedly enhanced with increasing SWNT length, which augments the interfacial adsorption capacity of the composite system and facilitates heat transfer. Concurrently, the thermal conductivity of the composites rises with the elongation of the SWNTs. Longer SWNTs can establish a robust thermal conductivity pathway, thereby enabling more efficient heat conduction along the axial direction of the SWNTs. This structural characteristics significantly enhances the thermal conductivity of the material and accelerates the transfer of heat.

Graphical Abstract

Based on molecular dynamics simulations, the effect of single-walled carbon nanotube (SWNT) length on the thermal properties of carbon nanotube/polyvinyl alcohol (SWNT/PVA) composites was systematically investigated. The simulation results demonstrate that the thermal conductivity of the composites exhibits a significant increasing trend with the increase in SWCNT length.