Chemical treatment and modification of multi-walled carbon nanotubes

It is shown that raw multi-walled carbon nanotubes (MWCNTs) can be cut into several hundred nanometer lengths by sonication in mixed acids. The resulting shortened MWCNTs formed a stable dispersion state in the polar solvent without the help of surfactants. Toward chemical modification of MWCNTs, the condensation reaction of the shortened MWCNTs and various alkyldiamines was carried out and the products were investigated by the Fourier transform infrared (FT-IR) spectroscopy and the scanning electron microscope (SEM) measurements. (C) 2002 Elsevier Science B.V. All rights reserved.