Conductance of carbon nanotubes

Because direct calculation of thermal conductivity is difficulty 1], experimental measurements on composites with nanotubes aligned in the matrix could be a first step for addressing the thermal conductivity of carbon nanotubes. High on-axis thermal conductivities for CCVD high-temperature treated carbon fibers have been obtained, but have not reached the in-plane thermal conductivity of graphite (ref. [3], Fig. 5.11, p. 115). We expect that the radial thermal conductivity in MWNTs will be very low, perhaps even lower than the c-axis thermal conductivity of graphite. 

Meincke O, Kaempfer D, Weickmann H, Friedrich C, Vathauer M, Warth H (2004). Mechanical properties and electrical conductivity of carbon-nanotube filled polyamide-6 and its blends with acrylonitrile/butadiene/styrene. Polymer 45 739-748. 

Fig. 4.13 (a) Semilogarithmic plot of conductivity versus the nanotube content (wt%) in poly(phenylene vinylene-co-2,5-dioctoxy-m-phenylene vinylene) (PMPV) [2]. (b) Frequency dependent conductivity of carbon nanotubes at different wt% in PmPV (filled symbols) and polyvinyl alcohol (PVA) (unfilled symbols) based composites [250]. 

M. M. S. Fakhrabadi, A. Allahverdizadeh, V. Norouzifard, B. Dadashzadeh, Effects of boron doping on mechanical properties and thermal conductivities of carbon nanotubes., Solid State Communications, vol. 152, pp. 1973-1979, 2012. 

Z. Hana, A. Fina, Thermal conductivity of carbon nanotubes and their polymer nanocomposites A review, Progress in Polymer Science, vol. 36, p. 914-944, 2011. 

Electrical conductivity of the carbon nanotubes shows a quantized property of an extremely thin one-dimensional wire. As predicted by theory, the conductance of carbon nanotubes is found to be ballistic. The advantage in... 

The electrical conductance of carbon nanotubes is sensitive to the chemical environment of the tubes. A large difference in the electrical conductance is observed for the carbon nanotubes in the presence of air and oxygen atmosphere. " " It is possible to tune the electrical conductance of carbon nantubes reversibly using adsorbent gas molecules. The carbon nanotubes were also used to increase the conductance of a conjugated polymer for the development of electroluminescence polymer-nanocomposites. " ... 

Berber, S., Y.K. Kwon, and D. Tomanek, Unusually High Thermal Conductivity of Carbon Nanotubes. Physical Review Letters, 2000. 84 p. 4613. 

The electric conductivity of carbon nanotubes is largely influenced by the presence of defects. Even effects as modest as axial strain with bond expansion change the band structure. Stone-Wales defects and other imperfections diminish the electric conductivity as well. This effect is especially pronounced for defects with two adjacent vacancies. The resistance of a 400 nm long SWNT, for example, increases by a factor of 1000 if the tube bears as little as 0.03% of these double vacancies. Single vacancies, on the other hand, do not cause such dramatic changes. In any case, however, the free path of the electrons is reduced considerably by the defects (in parts down to a few nanometers). Still, due to the multitude of existing conduction channels, this has no large influence on the overall conductivity. 

Barrau, S., Demont, R, Peigney, A., Laurent, C., and Lacabanne, C., dc and ac conductivity of carbon nanotubes-polyepoxy composites. Macromolecules, 36, 5187-5194 (2003a). 

Volkov, A., Shiga, T., Nicholson, D., Shiomi, J., Zhigilei, L. Effect of bending budding of carbon nanotubes on thermal conductivity of carbon nanotube materials. J. Appl. Phys. Ill, 053,501 (2012). doi 10.1063/1.3687943... 

Metal matrix nanocomposites are those having metal as the continuous phase or matrix and other nanoparticles like carbon nanotube as the reinforced materials. These types of composites can be classified as continuous and noncontinuous. One of the more important nanocomposites is Carbon nanotube reinforced metal matrix composite, which is an emerging new material with the high tensile strength and electrical conductivity of carbon nanotube materials. In addition to carbon nanotube metal matrix composites, boron nitride reinforced metal matrix composites and carbon nitride metal matrix composites are the new research areas on metal matrix nanocomposites [9,10]. 

Wescott, J. T., Kung, R, and Maiti, A. 2007. Conductivity of carbon nanotube polymer composites. Applied Physics Letters 90 033116. 

Clancy, T. C. and Gates, T. S. 2006. Modeling of interfacial modification effects on thermal conductivity of carbon nanotube composites. Polymer 47 5990-5996. 

Berber S, Kwon Y K and Tomanek D (2000) Unusually high thermal conductivity of carbon nanotubes, Phys Rev Lett 84 4613-4616. 

The electrical conductivity of carbon nanotubes in insulating plastics is a topic of considerable interest. The potential applications include electromagnetic... 

Hida S, Shiga T, Maruyama S, Elliott JA, Shiomi J (2012) Influence of thermal boundary resistance and interfacial phonon scattering on heat conduction of carbon nanotube/polymer composites. Trans Jpn Soc Mech Eng Part B 78(787) 634-643 Hilmi Y, Seyhana TA, Servet T, Metin T, Wolfgang B, Karl S (2010) Electric field effects on CNTs/vinyl ester suspensions and the resulting electrical and thermal composite properties. Compos Sci Technol 70(14) 2102-2110... 

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