繊維学会誌
Online ISSN : 1884-2259
Print ISSN : 0037-9875
64 巻, 1 号
選択された号の論文の40件中1~40を表示しています
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  • Haruka Kuwayama, Hidetoshi Matsumoto, Kenji Morota, Mie Minagawa, Akih ...
    2008 年 64 巻 1 号 p. 1-4
    発行日: 2008年
    公開日: 2008/03/08
    ジャーナル フリー
    Nanotextured polymer coatings were prepared on aluminum substrates by electrospray deposition (ESD) from poly(ethylene oxide) (PEO) solution. By controlling the size of deposits on the substrate, it is possible to change coloring of coatings — red, orange, yellow, green, and blue, — due to thin-film interference. These results indicate that the ESD method is a useful option for preparing optical coatings.
  • 奥崎 秀典, 高橋 卓己, 原 雄介, 厳 虎
    2008 年 64 巻 1 号 p. 5-10
    発行日: 2008年
    公開日: 2008/03/08
    ジャーナル フリー
    Unlike conventional electrospun polymer fibers deposited on a target electrode as a randomly oriented mesh, poly(p-xylenetetrahydrothiophenium chloride) (PXTC), a precursor of poly(p-phenylenevinylene) (PPV), was electrospun into centimeters-long yarns vertically on the surface of the electrode but parallelly to the electric field. The formation of the yarn was strongly influenced by the concentration, applied voltage, and relative humidity. The subsequent thermal conversion of thus-electrospun PXTC yarns was carried out at 250°C for 12 h in a vacuum and resulted in the uniaxially aligned PPV nanofibers with an average diameter of 150 nm. The applied voltage increased orientation of PPV nanofibers along the axis of the yarn, while the distribution of fiber diameter was less dependent on the applied voltage. Wide-angle X-ray diffraction analysis indicated that the PPV nanofibers exhibited paractistalline structure with crystallinity and crystallite size of 45% and 75Å, respectively. Furthermore, doping with sulfuric acid changed the color from yellowish brown to black and brought about a significant increase in the electrical conductivity of the PPV nanofiber yarn.
  • 桂 博史, 小山 俊樹, 市川 結, 谷口 彬雄
    2008 年 64 巻 1 号 p. 11-14
    発行日: 2008年
    公開日: 2008/03/08
    ジャーナル フリー
    Effects of carbon nano-fabric (CNFbc) as a nano-current-collect-layer on performances of direct methanol fuel cells (DMFCs) were determined. CNFbc was made using the electro-spinning method. CNFbc with an average diameter of 130 nm was placed between a cathode diffusion layer and a cathode catalyst layer. By using CNFbc with thickness of 27±2 μm DMFC, the maximum power density was improved from 46 to 74 mW cm-2 at the cell temperature of 60°C. From SEM images of cross sections of the membrane-electrode-assemblies, it was observed that the CNFbc interlayer has closely contact with both the cathode catalyst layer and the diffusion electrode. By using the CNFbc interlayer the electrical conductivity as well as the cell voltage at 200 mA cm-2 in the DMFC increased to 1.4 times. These results showed that the CNFbc interlayer improved the DMFC performance by decreasing the contact resistance between the cathode catalyst layer and the diffusion electrode. On the other hand, it was also found that too many microbeads in CNFbc reduce the effects of CNFbc interlayer. It was proved that the uniform CNFbc interlayer has useful effects as a nano-current-collect-layer in the DMFC.
  • 後藤 卓真, 小滝 雅也, 佐藤 昌憲, 鋤柄 佐千子
    2008 年 64 巻 1 号 p. 15-19
    発行日: 2008年
    公開日: 2008/03/08
    ジャーナル フリー
    Nanofiber assemblies have large surface area to volume ratio and unique porous structure. We demonstrated the concept that nanofiber assemblies can be used as receptor for Infrared Spectroscopy (FT-IR) analysis. Polyacrylonitrile (PAN) nanofiber assemblies were fabricated via electrospinning for the receptor which had high transmittancy in the entire wave number range. Two aqueous solutions, i.e. crystal violet (CV) and p-nitrophenol (p-N) solutions, were used as target samples for the transmission FT-IR analysis. Calibration curves with high correlation coefficient were obtained using PAN nanofiber assemblies. However, it was found that the correlation coefficient was dependent on chemical structure of the target molecules, i.e. lower correlation coefficient was obtained in the case of the p-N solution which had a lower molecular weight and a hydrophilic group.
  • 金 周瑢, 李 スミン, Jong Chul Park, 渡辺 義見, 金 翼水
    2008 年 64 巻 1 号 p. 20-23
    発行日: 2008年
    公開日: 2008/03/08
    ジャーナル フリー
    Nano web has various types of pore and pore size according to manufacturing condition. So, it is necessary to investigate the structure and mechanism of the web using mathematical method. First of all, nano web images were taken form SEM in order to make algorithm. Then we used a multi-layer stochastic model that includes the correlation between random arbitrary measurement lengths. Correlation functions of arbitrary measurement lengths are derived directly from the variance-length curve given without requiring any further information. Use of the correlation functions has more advantages over the traditional variance-length curves. First, they represent a yarn diameter (or mass) profile both in scale (resolution) and frequency (periodicity) rather than in scale only which is in the case for variance-length curves. Second, periodicities hidden in seemingly irregular signals are easily detected and revealed by the correlation functions. It is also beneficial that the functions are readily available from a variance-length curve without further efforts for measurement and analysis.
  • Yoshihiro Yamashita, Frank Ko, Hajime Miyake, Akio Higashiyama
    2008 年 64 巻 1 号 p. 24-28
    発行日: 2008年
    公開日: 2008/03/08
    ジャーナル フリー
    We examined the applicable developments of the electrospinning device and the conditions for producing nanofiber on some polymers within the range of lab-scale to manufacturing. It is understood that the use of multi-nozzle heads is more effective than increasing the flow rate. The solution concentration is an important factor for the control of the fiber diameter of the nanofiber. Moreover, it has been understood the nanofiber that uses the electrospinning process is to apply it to medical, cosmetics, and sanitary goods.
ノート
  • Midori Takasaki, Hao Fu, Kazuhiro Nakata, Yutaka Ohkoshi, Toshihiro Hi ...
    2008 年 64 巻 1 号 p. 29-31
    発行日: 2008年
    公開日: 2008/03/08
    ジャーナル フリー
    We used a CO2 laser as a heat source to avoid thermodegradation in the melt-electrospinning process (termed “laser electrospinning” (LES)). Nylon 6, polypropylene, poly (ethylene terephthalate) and poly (L-lactide-co-ε-caprolactone) fiber webs were prepared by the LES. For Nylon 6 and poly (L-lactide-co-ε-caprolactone), fibers having average diameters of approximately 1 μm and a coefficient of variation (CV) of no more than 20% were obtained. The effects of the applied voltage and laser power on the diameter of the PET fibers were investigated. The average diameter of the electrospun PET fibers decreased with a decrease in the applied voltage; however, using an applied voltage that was too low caused thermodegradation. The average diameter decreased with an increase in laser power. Above a certain laser power, however, shot particles and large deviations in the fiber diameter were observed.
  • 中山 篤, 高橋 良輔, 濱野 翼, 吉岡 太陽, 辻 正樹
    2008 年 64 巻 1 号 p. 32-35
    発行日: 2008年
    公開日: 2008/03/08
    ジャーナル フリー
    Nanofibers of poly(ethylene terephthalate) (PET), poly(butylene terephthalate) (PBT) and poly(ethylene 2,6-naphtalene dicarboxylate) (PEN) were prepared by electrospinning, and the resulting morphologies were investigated by polarizing optical microscopy, scanning electron microscopy and transmission electron microscopy. The major technological parameters (the concentration of polymer solution and the electrical field strength) which influence morphology of the obtained fibers were examined. PET, PBT and PEN nanofibers without beads were prepared by appropriately setting these parameters. In order to align and collect nanofibers parallel to each other, we used the homemade collector with parallel electrodes. The selected-area electron diffraction of nanofibers, which were drawn and/or heat-treated with being as-deposited on the collector, showed a well-developed fiber pattern.
Comprehensive Paper
  • 大川 浩作
    2008 年 64 巻 1 号 p. 36-44
    発行日: 2008年
    公開日: 2008/03/08
    ジャーナル フリー
    The present article describes our recent research works on the electrospinning of natural and bio-related polymeric materials. A synthetic poly(amino acids), poly(γ-benzyl-L-glutamate) (PBLG) and two natural polysaccharides, chitosan and cellulose, have been successfully spun into submicro- or nano-scaled fibers, which can be obtained as “electrospun non-woven fabrics (ESNWs)”. The major topics are (i) relationship between the chain conformation of PBLG in the pre-spun solution and the resulting post-spun morphology and mechanical property of PBLG-ESNWs, (ii) direct electrospinning of chitosan solution, preparation of the nanofibers, and post-spun treatment of the chitosan-ESNWs, with respect to the polymer chemical properties, and (iii) preparation of cellulose-ESNWs composed of the nano-scaled fibrous network and biomedical application as drug-carrier and releasing materials. Finally, technological aspects of the industrial application of these ESNWs were discussed, enclosing with perspectives for the future research subjects and possible applications.
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