Mechanics of buckled carbon nanotubes on elastomeric substrates

The buckling of carbon nanotubes (CNTs) on elastomeric substrates is studied in this paper. Simple expressions of the buckle wavelength and amplitude and the critical strain for buckling are obtained analytically. For single-walled CNTs, the wavelength is proportional to the CNT radius to the 3/4 power, while it increases linearly with the number of walls for multiwalled CNTs. For two parallel CNTs on the surface of the elastomeric substrate, there exists a critical spacing below which the two CNTs interact and buckle together, adopting the same wavelength. This cobuckling wavelength is very close to the wavelength for the larger CNT to buckle independently, i.e., the larger tube dominates the coupled buckling. (C) 2008 American Institute of Physics.