Sheet-type heaters were prepared using FKM rubber (fluoroelastomers composed of vinylidene fluoride and other fluoroalkenes) as a matrix with carbon black, multi-walled carbon nanotubes and cup-stacked carbon nanotubes as fillers. The electrical resistivity, thermal expansion, PTC (positive temperature coefficient) effects and filler dispersion properties were evaluated. The results showed that the nanocarbons were dispersed homogeneously and that the temperature dependence of the electrical resistivity could be controlled by the addition of nanocarbon fillers. The optimum PTC effects were observed for the samples with cup-stacked carbon nanotubes heat-treated at 1500°C.

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Exfoliated carbon fibers (ExCFs) obtained through rapid heat-treatment of intercalation compounds of carbon fibers had changed to the bundle of thin filament. In one of applications of its ExCFs, it was tried to nanocomposite where the application of Carbon nano tube (CNT) made an attempt. Preparation of composite using Nylon 6 and the ExCFs as the matrix and fillers was carried out by the injection molding. As the result, it became clear that addition of the ExCFs as fillers could be reinforced the matrix. Bending stress and elastic modulus of composite reinforced by the ExCFs increased around 50% with increasing in addition of the ExCFs in comparison with blank. It became clear that the ExCFs also exhibited better field emission characteristic at small-applied voltage in the case of an electrode material of field emission display (FED). Its field emission characteristics surpassed the case which CNT was applied to the electrode. Future applications were expected to the ExCFs.

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Recent advances in surface grafting of polymers onto nanocarbons, such as carbon black, carbon nanotube and nanofibers, carbon microcoil, nano-diamond, and C₆₀ fullerene, are reviewed. The grafting of polymers onto these surfaces was achieved by (1) “grafting onto” method, (2) “grafting from” method, (3) “polymer reaction” method, and (4) “stepwise growth” method by dendrimer synthesis methodology. For the grafting of polymers, surface functional groups, such as carboxyl and phenolic hydroxyl groups was used as grafting sites. These functional groups were converted into various initiating groups and surface initiated graft polymerization was achieved. The graphene sheet (polycondensed aromatic rings) of nanocarbons was used as grafting sites by using ligand-exchange reaction with polymers containing ferrocene moieties. The radical trapping activity of nanocarbon surfaces was also used for the grafting of polymers. Dispersibility in solvents for good solvents of grafted polymer was remarkably improved by the surface grafting of polymers onto nanocarbon surfaces. Other properties of polymer-grafted nanocarbons are also reviewed.

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Many reports discuss the unique electronic, optical and magnetic properties of fullerene molecules. Such properties originate in their special molecular structure, which is spherical and highly symmetric. Not only fullerene molecules, several interesting papers describe bulk fullerene crystals formed by simple crystal growth from solutions, and which contain solvent molecules. However, only a few studies have been made on the synthesis of uniform fullerene fine crystals with a size in nano/micrometer scale. The preparation of fullerene nano/microcrystals with a uniform size and shape would permit the control of their specific electronic energy levels and the totally new properties. Thus, we have attempted this research, using reprecipitation method developed in our laboratory. By changing simply experimental conditions such as the selection of solvents, we have obtained various unexpected and unique shapes of C₆₀ nano/microcrystals and with surprisingly monodispersed size.

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Carbon nanotube is scientifically quite interesting material because of its structural feature and various new quantum transport properties. By applying the feature of the narrow wire structure, the high sensitive bio sensor becomes possible. In the present paper, the specific quantum transport in carbon nanotube, and two kinds of applications of carbon nanotube to bio sensor will be shown.

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KAPTON films with and without adding small amounts of metallic compounds (0.1~2 at% as metal) were carbonized at 800~1200°C for 1 h in nitrogen and capacitance was measured in sulfate solutions by cyclic voltammetry. Nitrogen containing carbons derived from the film without additives had low specific surface area (S_BET < 90 m²g⁻¹) and the capacitance (C_T) was lower than 35 F g⁻¹. The capacitance normalized by S_BET (C_SP), however, reached as high as 0.77 F m⁻², and decreased with decreasing nitrogen content (W_N), indicating pseudocapacitance due to nitrogen. The correlation between C_SP and a proportion of particular nitrogen species on the surface was not observed. Except for silicone, the addition of compounds of Fe(II), Co(II), Ni(II) and Ti(IV) increased S_BET:S_BET increased with increasing amount of additives. The C_SP value for the products at 850°C varied depending on the additives, and the products were grouped under a) nitrogen containing carbons mainly showing pseudocapacitance due to nitrogen, b) iron containing carbons showing redox peaks, and c) carbons having relatively high S_BET (around 400 m²g⁻¹) and mainly showing the electric double layer capacitance.

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