NIPPON GOMU KYOKAISHI
Print ISSN : 0029-022X
Search
Advanced search
OR
Browse
Search
Volume 90, Issue 1
Displaying 1-5 of 5 articles from this issue
Show all abstracts
    • |<
    • <
    • 1
    • >
    • >|
General Reviews
  • Magnetorheological Effect for Bimodal Magnetic Elastomers
    Kazushi NAGASHIMA, Tetsu MITSUMATA
    2017 Volume 90 Issue 1 Pages 3-8
    Published: 2017
    Released on J-STAGE: March 17, 2017
    DOIhttps://doi.org/10.2324/gomu.90.3
    JOURNAL FREE ACCESS
    Show abstractHide abstract

    Magnetic soft materials such as magnetic gels or elastomers demonstrate drastic changes in the viscoelasticity synchronizing with the application of magnetic fields. The change in the viscoelasticity for magnetic soft materials is greatly enhanced by an addition of nonmagnetic particles causing by the stress transfer among imperfect chains of magnetic particles via nonmagnetic one. In this review, we survey the magnetic response of viscoelasticity for bimodal magnetic elastomers containing nonmagnetic particles, and the mechanism of the enhanced magnetic response has been explained.

    View full abstract
    Download PDF (1797K)
  • Block Copolymer-based Supramolecular Elastomers
    Atsushi NORO, Takato KAJITA, Yushu MATSUSHITA
    2017 Volume 90 Issue 1 Pages 9-13
    Published: 2017
    Released on J-STAGE: March 17, 2017
    DOIhttps://doi.org/10.2324/gomu.90.9
    JOURNAL FREE ACCESS
    Show abstractHide abstract

    Block copolymer-based supramolecular elastomer is one of the thermoplastic elastomers composed of glassy block A and melt hydrogen-bonded block B, both of which are connected to each other by a covalent bond. Such a block copolymer-based supramolecular elastomer can be prepared via living polymerization followed by solvent-casting. Poly(4-vinylpyridine)-b-[poly(butyl acrylate)-co-polyacrylamide]-b-poly(4-vinylpyridine) triblock copolymer serving as a supramolecular elastomer showed better mechanical properties than poly(4-vinylpyridine)-b-poly(butyl acrylate)-b-poly(4-vinylpyridine) triblock copolymer as a conventional thermoplastic elastomer without hydrogen bonding functional groups, in spite of having almost the same degree of polymerization of a glassy end block/a melt middle block and the total average molecule weight. The much better mechanical properties were attained when the triblock copolymer with larger melt middle block was used. Furthermore, if an incorporation ratio of hydrogen bonding functional groups into a melt middle block is increased, the maximum stress σmax increases while the elongation at break εb decreases; therefore, we found that the best mechanical properties were attained at the optimum incorporation ratio.

    View full abstract
    Download PDF (778K)
Advanced Course on Rubber Science and Technology
  • Variation of the States of Rubber
    5. Aging of Tire Parts in the Field: 2. Truck and Bus Tires
    Asahiro AHAGON
    2017 Volume 90 Issue 1 Pages 14-18
    Published: 2017
    Released on J-STAGE: March 17, 2017
    DOIhttps://doi.org/10.2324/gomu.90.14
    JOURNAL FREE ACCESS
    Show abstractHide abstract

    Property changes of TBR tire parts used in the practical field were characterized by means of log λb vs. log M100 mapping method, which was found to be useful in classification of aging patterns obtained by laboratory oven aging into the Types I ~ III. The aging conditions in tires, those brought about Type I aging pattern, were considered to agree with those found in the laboratory aging tests. The property changes were brought about by crosslinking reaction at relatively lower temperature in the presence of oxygen. Type II and III aging patterns were also observed in the aged tire after the field use. These variations of the aging patterns were generated by diffusion-limited oxidation under the high temperature condition and the mechano-chemical reactions due to the mechanical impact or large deformation of rolling tires.

    View full abstract
    Download PDF (901K)
Activity Report
Technical Note
    • |<
    • <
    • 1
    • >
    • >|
feedback
 Top