Published on Tuesday May 12, 2009
Members of the Nano Materials Group (NMG) and Mechanics of Microstructure Group (MMG) will publish a paper, "Viscoelasticity and high buckling stress of dense carbon nanotube brushes," in the July 2009 issue of Carbon. Authors include Siddhartha Pathak, Ph.D. '09, Z. Goknur Cambaz, Ph.D. '07, Yury Gogotsi, Trustee Chair Professor of Materials Science & Engineering and leader of the NMG, and Professor Surya Kalidindi, leader of the MMG.
The paper reports on the mechanical behavior of a dense brush of small-diameter (1-3 nm) noncatalytic multiwall (2-4 walls) carbon nanotubes (CNTs), with ~10 times higher density than CNT brushes produced by other methods. Under compression with spherical indenters of different radii, these highly dense CNT brushes exhibit a higher modulus (~17- 20 GPa) and orders of magnitude higher resistance to buckling than vapor phase deposited CNT brushes or carbon walls. The authors also demonstrate the viscoelastic behavior, caused by the increased influence of the van der Waals' forces in these highly dense CNT brushes, showing their promise for energy-absorbing coatings.