Title: A Micromechanics Model for the Thermal Conductivity of Nanotube-Polymer Nanocomposites

Gary D. Seidel a, Dimitris C. Lagoudas
Department of Aerospace Engineering
Texas A&M University
College Station, TX 77843-3141

Journal of Applied Mechanics -- 2008 -- Volume 75, Issue 4, pp. 041025-1-9

Abstract
A micromechanics approach for assessing the impact of an interfacial thermal
resistance, also known as the Kapitza resistance, on the effective thermal conductivity
of carbon nanotube-polymer nanocomposites is applied, which includes both
the effects of the presence of the hollow region of the carbon nanotube (CNT) and
the effects of the interactions amongst the various orientations of CNTs in a random
distribution. The interfacial thermal resistance is a nanoscale effect introduced
in the form of an interphase layer between the carbon nanotube and the polymer
matrix in a nanoscale composite cylinder representative volume element to account
for the thermal resistance in the radial direction along the length of the nanotube.
The end effects of the interfacial thermal resistance are accounted for in a similar
manner through the use of an interphase layer between the polymer and the CNT
ends. Resulting micromechanics predictions for the effective thermal conductivity
of polymer nanocomposites with randomly oriented CNTs, which incorporate input
from molecular dynamics (MD) for the interfacial thermal resistance, demonstrate
the importance of including the hollow region in addition to the interfacial thermal
resistance, and compare well with experimental data.

Key words: A. Carbon Nanotube, B. Nanocomposite, C. Thermal Conductivity,
D. Micromechanics, E. Composite Cylinders