Thermal Conduction in Aligned Carbon Nanotube–Polymer Nanocomposites with High Packing Density

TLDR

Nanostructured composites containing aligned carbon nanotubes are promising interface materials for electronic systems and thermoelectric power generators. The study reports the first data on thermal conductivity of densified, aligned multiwall CNT nanocomposite films across a range of CNT volume fractions. The authors investigate how CNT density influences thermal conduction by considering boundary resistances, defect concentrations, and possible suppression of phonon modes. Thermal conductivity rises nonlinearly with CNT volume fraction, more than doubling at 1 vol % and reaching up to an 18‑fold increase at 17 vol %.

Abstract

Nanostructured composites containing aligned carbon nanotubes (CNTs) are very promising as interface materials for electronic systems and thermoelectric power generators. We report the first data for the thermal conductivity of densified, aligned multiwall CNT nanocomposite films for a range of CNT volume fractions. A 1 vol % CNT composite more than doubles the thermal conductivity of the base polymer. Denser arrays (17 vol % CNTs) enhance the thermal conductivity by as much as a factor of 18 and there is a nonlinear trend with CNT volume fraction. This article discusses the impact of CNT density on thermal conduction considering boundary resistances, increased defect concentrations, and the possibility of suppressed phonon modes in the CNTs.