Netsu Sokutei

Influence of Solid Surface on the Thermal Polymerization of Amphiphilic Monomers in Micro DSC Measurements

Yoshio Shibasaki

1993 Volume 20 Issue 2 Pages 61-65
Published: April 30, 1993
Released on J-STAGE: September 07, 2009

DOIhttps://doi.org/10.11311/jscta1974.20.61

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Influence of solid surface on the addition polymerization of two amphiphilic compounds containing different functional groups (C=C or C≡C-C≡C) nearby polar head groups has been studied. In the addition polymerization, a solid surface seems to effect on both of initiation and propagation reactions, or on either one, and hence acceleration or suppression of the polymerization should be caused. In this study, mechanisms for suppression of polymerization of N-octadecyl acrylamide (ODAAm) and heptadeca-2, 4-diynoic acide (HD-2, 4-DA) by the surface effect of aluminium pan were examined comparing their γ-ray irradiation postpolymerization with the thermal polymerization in micro DSC measurements. In the polymerization of ODAAm, it was found that the initiation reaction was predominantly suppressed by the surface effect, because this monomer polymerized easily when free radicals had been generated previouly by γ-ray irradiation. The initiation reaction of HD-2, 4-DA also seems to be affected by anchoring of COOH groups on the aluminium surface.

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Thermal Solid/Gas Reactions of the Triruthenium Cluster [Ru₃(μ₃-O)(μ₂-CH₃COO)₆(CO)(L)₂]

Kenzo Nagase, Hiroko Yokobayashi, Akiyoshi Watanabe, Hajime Ishikawa, ...

1993 Volume 20 Issue 2 Pages 66-71
Published: April 30, 1993
Released on J-STAGE: September 07, 2009

DOIhttps://doi.org/10.11311/jscta1974.20.66

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The elimination and substitution reactions of the terminal ligands L(H₂O, CH₃OH and pyridine) of the triruthenium cluster in the solid state were studied mainly by thermogravimetric analysis in nitrogen gas, vacuum, methanol vapor and pyridine vapor with various heating rates. The reaction schemes for the solid/gas reactions were presented. It was suggested that one or two vacant sites in the terminal positions can be formed during the elimination of the terminal methanol or water, which may be an active site for solid/gas rections.

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Mössbauer Effect Study of Structural Changes in Fe-Al-Si-Ni Thin Films

Masahiro Miyazaki, Takayuki Komatsu, Kazumasa Matusita

1993 Volume 20 Issue 2 Pages 72-81
Published: April 30, 1993
Released on J-STAGE: September 07, 2009

DOIhttps://doi.org/10.11311/jscta1974.20.72

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Fe-Al-Si-Ni magnetic films with a thickness of 1μm were deposited on crystallized-glass substrates by rf magnetron sputtering, and the changes in magnetic properties and microscopic structural changes in the films due to the annealing were investigated. The films annealed at 500°C exhibit excellent soft magnetic properties as for recording head materials. Furthermore, the films with high saturation magnetic-flux densities of 1.48T were obtained. It was found through conversion electron Mössbauer spectroscopy that the disorder structure of α-type in as-sputtered films transforms into the ordered structure consisting of a mixture of B2-and DO₃-types at the temperature of 500°C.

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High Pressure Differential Thermal Analysis of Ultra-pure Unsaturated Fatty Acids

Nobuyasu Hiramatsu, Tohru Inoue

1993 Volume 20 Issue 2 Pages 82-88
Published: April 30, 1993
Released on J-STAGE: September 07, 2009

DOIhttps://doi.org/10.11311/jscta1974.20.82

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The effect of hydrostatic Pressure on the polymorphic transformation and melting of cis-unsaturated fatty acids, palmitoleic acid (POA), oleic acid (OA), asclepic acid (APA), petroselinic acid (PSA) and erucic acid (EA), were investigated by means of a high-pressure differential thermal analysis. The temperature range of α form of OA and POA becomes wider as the pressure is increased, which is the same tendency as the high pressure phase of polyethylene. On the contrary, those of α₁ form of EA and high pressure crystallized α_p form of APA are narrowed by increasing pressure. This is similar trend to the hexagonal (rotator) phase of n-alkane. The values of ΔV on melting and conformational order-disorder transitions of ω chain were estimated from the Clausius-Clapeyron equation. The ΔV on γ-α transitions for POA, OA, and APA are almost the same (5.6-5.9cm³/mol), but that on γ₁-α₁ transition for EA is larger than those for the former acids. New polymorphs were formed for APA by the melt-crystallizatoin under high pressure above about 110MPa.

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Thermal Analysis of Superconducting Oxides

Masae Kikuchi

1993 Volume 20 Issue 2 Pages 89-100
Published: April 30, 1993
Released on J-STAGE: September 07, 2009

DOIhttps://doi.org/10.11311/jscta1974.20.89

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A review of the thermal analysis of high-T_c superconductiung oxides is presented. Search for synthesis condition, the determination of oxygen contents by hydrogen reduction, the absorption and desorption of oxygen, the relation between oxygen contents and superconductivity or structure, and the thermal stability in ambient gas, are briefly discussed.

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Thermal Properties of Nylon/Nylon and Thermotropic Liquid Crystalline Polymer/Nylon Blends

Nobuo Ogata

1993 Volume 20 Issue 2 Pages 101-104
Published: April 30, 1993
Released on J-STAGE: September 07, 2009

DOIhttps://doi.org/10.11311/jscta1974.20.101

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