A carbon nanotube has a strength of several tens of GPa, an elastic modulus of several hundreds of TPa, and excellent electrical and thermal conductivities, which surpass those of a-conventional carbon fiber. Various researches on processes for fabrication of carbon nanotube bulk material have been performed over many years. Particularly, research on carbon nanotube fibers among carbon nanotube bulk materials has been performed by the R. H. Baughman group in U.S. (M. Zhang et al, Science 306, 1358 (2004)) and the S. Fan research group in China (X. Zhang et al, Adv. Mater. 18, 1505 (2006)), but they were not able to obtain any results showing own characteristic properties of the carbon nanotubes due to weak binding strength between the carbon nanotubes. Thus, to harness the excellent own characteristic properties of the carbon nanotubes, improvement in performance of the carbon nanotube bulk material is required.
USPTO Backgrounds
USPTO Backgrounds