Carbon nanotubes bending resistance

CNTs are valued for their novel properties mechanical strength, chemical inertness, electronic and thermal conductivity. Mechanical properties of CNTs, especially their extreme flexibility and strength equal to steel with one-sixth the mass, is most impressive. An excellent resistance of carbon nanotubes to bending has been observed experimentally and studied theoretically. CNTs are not nearly as strong under compression. Due to their hollow structure, they undergo buckling when placed under compressive, torsional or bending stress.16... 

In any case, the mechanical loading capacity of the material increases upon the addibon of carbon nanotubes. The composite s properbes are considerably enhanced, especially with regard to tensile or bending sbess. In workpieces charged with pressure, on the other hand, nanotubes do not convey much benefit as their resistance to compression along the axis is limited. 

Carbon nanotubes are a new allotropic form of caibon and possess interesting physicochemical properties. Their chance discovery was a result of an enormous interest in fullerenes. Carbon nanotubes are built of graphene layers and can assume single- or multi-wallet structures [23,25,35]. Chemical modifications of nanotubes in both open terminated areas and on outer and inner walls create many possibilities. Prospective and present applications of nanotubes depend on their physicochemical properties, such as density, resistance to stretching and bending, thermal and electrical conductivity, field emission, as well as resistance to temperature. Good adsorption properties of nanocarbon materials contribute to their extensive practical application. 

Heath discovered that hexane solutions of Ag nanoparticles, passivated with octanethiol, formed spontaneous patterns on the surface of water when the hexane was evaporated, " and has prepared superlattices of quantum dots. " Lieber has investigated the energy gaps in metallic single-walled carbon nanotubes and has used an atomic-force microscope to mechanically bend SWNT in order to create quantum dots less than 100 nm in length. He found that most metallic SWNT are not true metals, and that by bending the SWNT, a defect was produced that had a resistance of 10 to 100 kfl. Placing two defects less than 100 nm apart produced the quantum dots. 

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