2011 Annual Meeting

(361d) A More Realistic Model for the Study of Thermal Conductivity of Nanocomposites

Author

Khoa N. D. Bui - Presenter, The University of Oklahoma


Calculating the thermal conductivity (Keff) for carbon nanotube-based nanocomposites is a challenging task due to the presence of thermal boundary resistance (TBR) as well as the randomness of dispersion state and of the geometry of carbon nanotubes (CNTs). It has been found that the TBR of carbon nanotube to carbon nanotube (TBRCNT-CNT) can be higher than the TBR between a nanotube and the surrounding matrix [1-3]. The effective medium theory is capable of calculating Keff assuming that the CNTs are in a perfect dispersion state and excluding the TBRCNT-CNT effect [4]. However, our previous work with CNTs modeled as stiff cylinders showed that the tendency of CNTs to create bundles and the TBRCNT-CNT can dramatically suppress Keff at high volume fraction of CNTs [5]. The CNTs are observed to have “worm-like” shape in reality [4] and no prior work has been reported in studying the effect of the curvature (expressed in terms of the persistence length of the CNTs) on the Keff of nanocomposites.

In this work, we will report on the development of a new algorithm allowing the generation of  CNTs with worm-like geometry in 3D, and with different persistence length. The use of these geometries in conjunction with off-lattice Monte Carlo simulations [3,5] in order to study the effective thermal properties of nanocomposites will be discussed.

References

[1] J.E. Peters, D.V. Papavassiliou, B.P. Grady, Macromolecules, 41 (2008) 7274-7277.

[2] S. Maruyama, Y. Igarashi, Y. Taniguchi, J. Shiomi, J. Therm. Sci. Tech., 1 (2006) 138-148.

[3] K. Bui, H. M. Duong, A. Striolo, and D. V. Papavassiliou, J. Phys. Chem. C, 115 (2011)10.

[4] C. W. Nan, G. Liu, Y. Lin, and M. Li, Applied Physics Letters, 85 (2004) 16.

[5] K. Bui, B. P. Grady and D. V. Papavassiliou, Chemical Physics Letters, doi:10.1016/j.cplett.2011.04.005 (2011).