Extraordinary chemical and physical properties of carbon nanotubes (CNTs) as well as the success of large-scale production by a catalytic chemical vapor deposition (CCVD) method, particularly with the use of a floating reactant technique, make them applicable in the fabrication of adsorbent, electrochemical electrode, and functional filler composite, etc at a possible low cost. Through judicious selection of transition metal, support materials and synthetic conditions (temperature, duration), it is possible to produce different types of CNTs such as multi-walled CNTs (MWCNTs), double-walled CNTs (DWCNTs) and single-walled CNTs (SWCNTs) selectively. In order to produce bulk quantities of CNT, a well-developed iron catalyst-based CCVD method so-called “Endo method” has been commonly used in the world. In this paper, we describe the synthetic techniques of various CNTs. The structural analysis will also be discussed in terms of nano-structure, and finally their practical applications of these CNTs will be described from the industrial point of view.

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Hydrocarbons such as oil and gas are critical resources for the functioning of human societies. Today, with the dearth of easy-to-reach reservoirs, the oil and gas industry is conducting more of its exploration and exploitation activities in difficult-to-reach and harsh environments. Key challenges in exploiting these new reservoirs include extremely high temperatures and pressures. The rubber composites obtained from the carbon nanotubes cellulation technology increases operational ratings from 175 °C and 140 MPa to 260 °C and 240 MPa for deeper, hotter conditions, and it is especially appropriate for deepwater reservoirs. We believe that our development of the sealing material to enhance oil recovery from deep, hot reservoirs may help double the R/P ratio. The cellulation technologies can be applied to various matrix composites such as metals, ceramics, and other polymers.

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Recent advances in surface grafting of polymers onto nanocarbon materials, such as carbon nanotube (CNT) and vapor grown carbon nanotube (VGCF), are reviewed. The grafting of polymers onto these surfaces was achieved by (1) the “grafting onto” method and (2) “grafting from” method. For the grafting of polymers, surface functional groups, such as carboxyl groups, previously introduced onto CNT surfaces by oxidation with nitric acid, were used as grafting sites. The grafting by “grafting onto” method was carried out by the reaction of the functional groups on CNTs with terminal functional groups of polymers to give polymer-grafted CNTs. Polycondensed aromatic rings (graphene) of CNT and VGCF were used as grafting sites by using ligand-exchange reaction with polymers containing ferrocene moieties in the presence of AlCl₃. The radical trapping activiity of CNT and VGCF surface was successfully used for the grafting of polymers. On the other hand, surface functional groups were converted into various initiating groups and surface initiated graft polymerization was achieved. The grafting of polymers with controlled molecular weight and narrow molecular weight distribution onto CNT by surface initiated living radical polymerization, such as atom transfer radical polymerization and nitroxide mediated radical polymerization were summarized.

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Fullerenes, first reported by Kroto, are the carbon materials which only carbons connect 60 or more. Since such greatly unique materials were discovered, researches of fullerenes have been addressed a lot. In this report, we had prepared the composites which added the fullerenes to thermoplastic polyurethanes and styrene block copolymers, and then investigated the relationship between structures and properties of composites by measuring tensile properties, dynamic mechanical analysis (DMA), differential scanning calorimetry (DSC) and atomic force microscopy (AFM).

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A boron nitride nanotube (BNNT) is a structural analog of a carbon nanotube (CNT). However, due to their colorless nature, superior thermal and chemical stabilities, straight shapes, superb rigidity and elasticity, BNNTs are an intriguing nanoscale material which may find interesting uses in nano-technology such as nano-scale assembly and polymeric nano-composites with potential to rival or even surpass CNTs. Thus, high-concentration dispersion and chemical modification of BNNTs are primary important to realize a viable polymer nanocomposite systems. By combining present dispersion methods, BNNT could be mixed in current polymer matrices such as polyamide, polyester and polyolefin. Here we report an effective strategy to disperse BNNTs homogeneously into a wide range of polymeric materials from engineering plastics to biomacromolecules and examples of high performance / functional nano composites that might be practically useful in industrial, especially for the engineering applications.

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