Vapor-grown carbon fiber

Carbon fibers derived from polyacrylonitrile present low heat characteristics, so these type of composites are suited for applications where this aspect is mandatory. The investigation of polymers reinforced with pitch-based carbon fibers, vapor grown carbon fibers, carbon foam, and CNTs having high thermal conductivities opens up significant new markets based on multiple potential applications. 

Suitable electrically conductive fillers include carbon black, carbon fibers, vapor grown carbon fibers, carbon nanotubes, metal fillers, conductive non-metal fillers, metal coated fillers, etc (7). 

Key Words—Carbon nanotubes, vapor-grown carbon fibers, high-resolution transmission electron microscope, graphite structure, nanotube growth mechanism, toroidal network. 

The anodic behavior of carbon materials, such as acetylene black, activated carbon, and vapor-grown carbon fiber, in LiC104/PC solution was studied by Yamamoto et al. [102]. Irreversible reactions, including gas evolution and disintegration, were mainly observed on that part of the surface occupied by the edge planes of the... 

Yamanaka I, Hashimoto T, Otsuka K (2002) Direct synthesis of hydrogen peroxide (>lwt%) over the cathode prepared from active carbon and vapor-grown-carbon-fiber by a new H2-O2 fuel cell system. Chem Lett 8 852-853... 

Regarding a historical perspective on carbon nanotubes, very small diameter (less than 10 nm) carbon filaments were observed in the 1970 s through synthesis of vapor grown carbon fibers prepared by the decomposition of benzene at 1100°C in the presence of Fe catalyst particles of 10 nm diameter [11, 12]. However, no detailed systematic studies of such very thin filaments were reported in these early years, and it was not until lijima s observation of carbon nanotubes by high resolution transmission electron microscopy (HRTEM) that the carbon nanotube field was seriously launched. A direct stimulus to the systematic study of carbon filaments of very small diameters came from the discovery of fullerenes by Kroto, Smalley, and coworkers [1], The realization that the terminations of the carbon nanotubes were fullerene-like caps or hemispheres explained why the smallest diameter carbon nanotube observed would be the same as the diameter of the Ceo molecule, though theoretical predictions suggest that nanotubes arc more stable than fullerenes of the same radius [13]. The lijima observation heralded the entry of many scientists into the field of carbon nanotubes, stimulated especially by the un-... 

M. Endo. Meeanisme de eroissanee en phase vapeur de fibres de earhone (Tlte growth mechanism of vapor-grown carbon fibers). PhD thesis. University of Orleans, Orleans, France, 1975. (in French). 

Vapor grown carbon fiber (VGCF) is the descriptive name of a class of carbon fiber which is distinctively different from other types of carbon fiber in its method of production, its unique physical characteristics, and the prospect of low cost fabrication. Simply stated, this type of carbon fiber is synthesized from the pyrolysis of hydrocarbons or carbon monoxide in the gaseous state, in the presence of a catalyst in contrast to a melt-spinning process common to other types of carbon fiber. 

Tibbetts, G.G., Vapor-grown carbon fibers status and prospects. Carbon, 1989, 27(5), 745 747. 

Tibbetts, G.G., Beetz, Jr., C.P., Mechanical properties of vapor grown carbon fibers,. 1. Appl. Phys 1987, 20, 292... 

Tibbetts, G.G., Endo, M. and Beetz, Jr. C.P., Carbon fibers grown from the vapor phase A novel material, SAMPE, Sept., Oct., 1986, 22(5). 

Jacobsen, R.L., Tritt, T.M. Guth, J.R., Ehrlich, A.C. and Gillespie, D.J., Mechanical properties of vapor-grown carbon fiber, Carbon, 1995, 33(9), 1217 1221 Brito, K.K., Anderson, D.P. and Rice, B.P., Graphilization of vapor grown carbon fibers, Proc, 34 - Inter. SAMPE Symp., 1989, 34(1), 190... 

Ting, J.-M. and Lake, M.L., Vapor-grown carbon-fiber reinforced carbon composites, Carbon, 1995, 33(5), 663 667... 

Dasch, C.J., Baxter, VV.J., and Tibbetts, G.G., Thermoplastic composites using nanometer-size vapor-grown carbon fibers. Extended Abstracts, 2Ist lliennial Conference on Carbon, 1993, pp. 82 83,... 

Katsumata,. M. and Endo, M, J.,Epoxy composites using vapor-grown carbon fiber... 

VAPOR-GROWN CARBON FIBERS AND PYROLYTIC CARBON NANOTUBES... 

Vapor-grown carbon fibers have been prepared by catalyzed carbonization of aromatic carbon species using ultra-fine metal particles, such as iron. The particles, with diameters less than 10 nm may be dispersed on a substrate (substrate method), or allowed to float in the reaction chamber (fluidized method). Both... 

Fig. 3. Vapor-grown carbon fibers obtained by substrate method w ith diameter ca. 10 /xrn (a) and those by floating catalyst method (b) (inserted, low magnification).

Pyrolytic carbon nanotubes from vapor-grown carbon fibers... 

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