1989 Fiscal Year Final Research Report Summary
Fourier Transform Infrared Spectroscopic Studies on Molecular Motions and Mechanisms of Degradation and Stabilization for Polymers
| Project/Area Number |
63470084
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| Research Category |
Grant-in-Aid for General Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Research Field |
高分子物性
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| Research Institution | Gunma University |
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Principal Investigator |
KOBAYASHI Shodo Gunma University, Faculty of Technology, Lecturer, 工学部, 講師 (60008448)
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| Co-Investigator(Kenkyū-buntansha) |
KURODA Shinichi Gunma University, Faculty of Technology, Assistant, 工学部, 助手 (60205250)
OSAWA Zenjiro Gunma University, Faculty of Technology, Professor, 工学部, 教授 (50008439)
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| Project Period (FY) |
1988 – 1989
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| Keywords | Molecular motion / FTIR spectra / Polytetrahydrofuran / Chemiluminescence / Engineering plastics / Degradation mechanism / Polyolefins / Photo-oxidative degradation |
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| Research Abstract |
[1]. Molecular Motions of Polymer Solids
(1) Molecular motions of polytetrahydrofuran and poly(tetramethylene sulfide) solids were studied by FTIR and X-ray diffraction methods. Infrared bands sensitive to molecular motions for each polymer were specified. In partially crystalline polymers the molecular motions in noncrystalline region exert influence on the Bragg reflections. Therefore various molecular motions in polymer solid can be detected by investigating the temperature dependences of interplanar spacing and half-width for each reflection.
(2)The changes in molecular conformation in each phase transition and the molecular motions of flexible side chains for the discotic liquid crystalline substance were determined.
[2]. Degradation reaction of polymer
(1) The chemilumineseence intensities were measured during the thermo-oxidative degradation of polyolefins such as polyethylene(PE), isotactic polypropylene (IPP), poly-4-methylpentene(P4MP), and polybutene(PB). The order of the thermal stability was as follows: PE>P40>MP>PB. The chemiluminescence intensity related closely to the changes in chemical structures. The effects of some commercial copper deactivators on the thermo-oxidative degradation of various polymers were evaluated by the chemiluminescence method.
(2)In the photodegradation of polyearbonate(pc)/poly(methyl methaerylate)(PMMA) blends, photo-Fries rearragement of PC occurs predominantly, and PC component retards the potodegradation of PMMA component.
(3) Photodegradation mechanisms of polycarbonate and poly(p-phenylene sulfide) have been studied by FTIR, UV, and ESR methods. In the photodegradation of PPS the cross linking structures are formed by the radical reaction initiated by the scission of C-S bonds, and the reaction is accelerated by the existence of O_2. Sulfur atoms on the main chain are oxidated in the air.
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