Kapton-type polyimide films containing 0.1 at% Ni (PI-0.1Ni) and 0.5 at% Fe (PI-0.5Fe) were prepared from polyamic acid and each metallocene, and carbonized at a heat treatment temperature (HTT) of 400 -1600°C in flowing argon. Nickelocene was reduced to Ni metal particles of less than 20 nm in diameter at 450°C by 1h treatment. The PI-0.1Ni started to decompose by about 200K lower than the film without additives (PI), while with PI-0.5Fe such effect was not observed. Further, with PI-0.1Ni a sharp carbon 002 peak around 2θ=26° was developed markedly with raising HTT from 1000 to 1600°C. With PI-0.5Fe, the 002 peak became sharp at HTT =1050°C, but the peak intensity and profile changed only slightly in a range of 1100 1600°C. In the 1600°C treated PI-0.1 Ni, fairly large areas with oriented hexagonal carbon layers and those with entangled ribbon-like structure were observed in the lattice images by TEM. A small number of tunnel-like holes (1-2 μm in diameter) were observed by SEM in the cross-section of the film, which suggested the movement of Ni metal particles during the heat treatment. The 1000°C treated PI-0.1Ni was not graphitized by 1 h treatment at 3000°C, suggesting the formation of so-called “TS carbon.” The present results showed that very small amounts of Ni are effective to the initial thermal decomposition of the polyimide and subsequent formation of turbostratic carbon, whereas Fe seemed to enhance the development of turbostratic carbon less effectively.

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We newly developed carbonized material board (CMB) by adhering of carbonized material powders with superfine natural fibers as binder. The superfine cellulose and collagen fibers were prepared from defiberized milk cartons and leather scraps with a grinder, respectively. The CMB adsorbed ammonia, formaldehyde and toluene gases from 2Oppm to almost Oppm within two hours. And it was confirmed that the CMB adsorbed and desorbed moisture depending on the relative humidity of the environment. When carbonized material powder was adhered with the superfine fibers, the function of carbonized material such as adsorption or humidity conditioning were maintained in the CMB.

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Carbon and graphite films were prepared from the laboratory-made Kapton-type polyimide film, and the electric conductivities parallel, σ_//, and perpendicular, σ_⊥, to the surface were measured at room temperature. Anisotropy of electric conductivity was observed even for the 700°C treated film and the ratio, σ_///σ_⊥, increased with raising heat treatment temperature (HTT). The carbon films formed at HTT=1200-1600°C showed nearly the same conductivity, and σ_///σ_⊥ in this range was 450-550. The conductivities and sailla σ_///σ_⊥ ratio increased with further raising HTT up to 2800°C. The structural changes of the films were also investigated by using XRD and TEM.

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Microbial pollution that takes place by microorganisms has produced various problems in industry and daily life. For example, contaminated water for washing food and contaminated drinking water in aircrafts became topics in connection with troubles in health. Novel antibacterial treatments have been expected to solve the problems up to now. The antibacterial activity on ceramic powders was pointed out with much attention as a new technique that can substitute for some conventional organic agents. And also, carbon materials containing ceramic fine particles showed effectiveness for growth inhibition and adsorption of bacteria. In the present paper, antibacterial activity of inorganic materials, such as CaO, MgO, ZnO and carbon materials containing these ceramics, is explained, and a mechanism of the activity is discussed.

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Vinyl-type polymers are attractive as precursor for carbon materials because of their high carbon content and good processability. If these polymers are exposed to a carbonization atmosphere, however a large mass loss and fusion usually take place. Thus, some additional treatment for enhancing the thermal stability of the polymers is required prior to carbonization, and this treatment is referred to as stabilization. Since most of vinyl-type polymers are thermally decomposed only at temperatures above their melting points, it is difficult to stabilize them with a low-temperature heat-treatment in air. It is known that the treatments with chemical agents can convert vinyl-type polymers to the thermal resistant polymers. The present authors have developed the novel production processes of carbon materials from various vinyl-type polymers by using a combination of chemical treatment and high-temperature heat-treatment. This paper reviews the structure and properties of viny-type polymer-based carbon materials.

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