Details of the Researcher

PHOTO

Ryo Mashita
Section
International Center for Synchrotron Radiation Innovation Smart
Job title
Specially Appointed Associate Professor(Research)
Degree
e-Rad No.
40977328

Research History 2

  • 2025/04 - Present
    Tohoku University　International Center for Synchrotron Radiation Innovation Smart　Special Appointed Associate Professor

  • 2007/04 - Present
    住友ゴム工業株式会社

Education 3

  • Kyoto University　Graduate School of Engineering　Department of Polymer Chemistry

    2013/04 - 2016/03

  • Kyoto University　Graduate School of Engineering　Department of Material Chemistry

    2005/04 - 2007/03

  • Kyoto University　Faculty of Engineering　School of Industrial Chemistry

    2001/04 - 2005/03

Professional Memberships 1

  • 日本放射光学会

Research Interests 1

  • ゴム、X線、中性子

Research Areas 1

  • Nanotechnology/Materials / Polymer materials /

Awards 2

  1. 第20回SPring-8産業利用報告会優秀発表賞

    2024/04　SPring-8利用推進協議会　X線4次元CT法を用いたタイヤゴム材料の破壊過程の観察

  2. ベストプレゼンテーション賞

    2007　日本レオロジー学会

Papers 20

  1. Fast local motions and their transitions in polybutadiene across the glass transition Peer-reviewed

    Tatsuya Kikuchi, Ryo Mashita, Tomomi Masui, Toshiji Kanaya, Hiroyuki Kishimoto, Kenji Nakajima

    Physical Review E　113　(6)　2026/06/16

    Publisher: American Physical Society (APS)

    DOI： 10.1103/tg7v-hw13 　

    ISSN： 2470-0045

    eISSN： 2470-0053

  2. Development of an automated X-ray tomography measurement system with a temporal resolution of 10 ms Peer-reviewed

    Ryo Mashita, Liang Xiaoyu, Ryosuke Ueda, Yasumasa Bito, Kentaro Kajiwara, Yoshimasa Urushihara, Hiroyuki Kishimoto, Wataru Yashiro

    Japanese Journal of Applied Physics　65　020904　2026/01/30

    DOI： 10.35848/1347-4065/ae350c 　

  3. New Insights into the Fracture Precursors of Rubber Reinforced with a Nanofiller Peer-reviewed

    Hiroki Ogawa, Ryo Mashita, Hiroyuki Kishimoto, Shunsuke Ono, Wataru Yashiro, Taizo Kabe, Hiroyasu Masunaga, Mikihito Takenaka

    Small Structures　2025/07/21

    Publisher: Wiley

    DOI： 10.1002/sstr.202500257 　

    ISSN： 2688-4062

    eISSN： 2688-4062

    More details Close

    Filler‐reinforced rubber materials are used in tires, belts, and other items indispensable to the daily lives of people. The characteristic required to realize a circular economy is an improved fracture resistance, i.e., a longer product lifetime. To improve the fracture resistance, understanding the fracture mechanism of materials is essential. Fracture results from the appearance of microscopic cavities, but the understanding of the heterogeneous structural deformation factors (fillers and molecular chains) responsible for cavities remains inadequate. Herein, the first capture of fracture precursor phenomena using simultaneous X‐ray scattering/absorption–computed tomography measurements is reported. As precursor phenomena, deformation induces a grain structure in which each grain has different alignment of silica particles and orientation of molecular chains, and exfoliation of molecular chains from the silica particle surface occurs between the grains. Capturing the precursor phenomena from the heterogeneity perspective provides new insight into the design of materials.

  4. Quasi-elastic γ-ray scattering study of α process under stretching in crosslinked rubber filled with silica via Mössbauer time-domain interferometry Peer-reviewed

    Ryo Mashita, Yoshitaka Yoda, Yasumasa Bito, Hiroyuki Kishimoto, Makoto Seto, Toshiji Kanaya, Makina Saito

    Interactions　245　(1)　2024/10/08

    Publisher: Springer Science and Business Media LLC

    DOI： 10.1007/s10751-024-02171-x 　

    eISSN： 3005-0731

  5. Microscopic Observation of the Anisotropy of the Johari–Goldstein-β Process in Cross-Linked Polybutadiene on Stretching by Time-Domain Interferometry Peer-reviewed

    Ryo Mashita, Makina Saito, Yoshitaka Yoda, Nobumoto Nagasawa, Yasumasa Bito, Tatsuya Kikuchi, Hiroyuki Kishimoto, Makoto Seto, Toshiji Kanaya

    ACS Macro Letters　13　(7)　847-852　2024/06/25

    Publisher: American Chemical Society (ACS)

    DOI： 10.1021/acsmacrolett.4c00274 　

    ISSN： 2161-1653

    eISSN： 2161-1653

  6. Broadband Quasielastic Scattering Spectroscopy Using a Multiline Frequency Comblike Spectrum in the Hard X-Ray Region Peer-reviewed

    Makina Saito, Masashi Kobayashi, Haruki Nishino, Toshiyuki Nishiyama Hiraki, Yoshiaki Honjo, Kazuo Kobayashi, Yasumasa Joti, Kyosuke Ozaki, Yasuhiko Imai, Mitsuhiro Yamaga, Tetsuya Abe, Nobumoto Nagasawa, Yoshitaka Yoda, Ryo Mashita, Takaki Hatsui, Yusuke Wakabayashi

    Physical Review Letters　132　(25)　2024/06/17

    Publisher: American Physical Society (APS)

    DOI： 10.1103/physrevlett.132.256901 　

    ISSN： 0031-9007

    eISSN： 1079-7114

  7. Insights into the cavitation morphology of rubber reinforced with a nano-filler Peer-reviewed

    Ryo Mashita, Yasumasa Bito, Kentaro Uesugi, Masato Hoshino, Ikuo Kageyuki, Hiroyuki Kishimoto, Wataru Yashiro, Toshiji Kanaya

    Scientific Reports　13　(1)　2023/04/10

    Publisher: Springer Science and Business Media LLC

    DOI： 10.1038/s41598-023-33137-8 　

    eISSN： 2045-2322

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    Abstract Notwithstanding the various uses of rubber, the fracture mechanism of filler-reinforced rubber remains unclear. This study used four-dimensional computed tomography (4D-CT) involving monochromatic synchrotron X-rays to examine the cavitation within silica-reinforced rubber quantitatively and systematically. The results suggested a threshold value of silica content for the cavitation morphology. Macroscopic fractures, such as those developed by void formation, occurred below the threshold value of silica content. Above this threshold, the density of rubber decreased but macroscopic voids rarely occurred. The lower-density rubber area in the high-silica-content rubber was reversible at the effective pixel size for 4D-CT. These results suggest that the growth of the damage points to macrosized voids could be stopped by the formation of a network of rigid polymer layers. This study allows the elucidation of the reinforcing mechanism and the cavitation morphology of filler-reinforced rubber.

  8. Microscopic observation of the effects of elongation on the polymer chain dynamics of crosslinked polybutadiene using quasi-elastic γ-ray scattering Peer-reviewed

    Ryo Mashita, Makina Saito, Yoshitaka Yoda, Hiroyuki Kishimoto, Makoto Seto, Toshiji Kanaya

    Journal of Synchrotron Radiation　29　(5)　1180-1186　2022/08/23

    Publisher: International Union of Crystallography (IUCr)

    DOI： 10.1107/s1600577522007998 　

    eISSN： 1600-5775

    More details Close

    A synchrotron-radiation-based quasi-elastic γ-ray scattering system has been developed that uses time-domain interferometry to observe microscopic polymer dynamics under uniaxial deformation. The stress-producing mechanism of crosslinked polybutadiene has been studied from a microscopic viewpoint. It was found that the mean relaxation time 〈τ〉 of the microscopic polymer motion observed over a relatively high temperature (T) range (i.e. T −1 < 0.0045 K−1) increased with elongation on both the intra- and intermolecular scales. Following an extensive strain dependence study, it was found that the strain dependences of both the intra- and intermolecular 〈τ〉 changed with the stress dependence. It was therefore suggested that 〈τ〉 increased due to the constraint of the local polymer chain motion caused by elongation. The local molecular dynamics of polymer chains under uniaxial deformation could be evaluated at intra- and intermolecular scales separately for the first time using our method.

  9. Effect of silica-nanoparticle fillers on the Johari-Goldstein-β process in polymer nanocomposites Peer-reviewed

    Makina Saito, Ryo Mashita, Toshiji Kanaya, Hiroyuki Kishimoto, Yoshitaka Yoda, Makoto Seto

    Hyperfine Interactions　242　(1)　2021/12/13

    Publisher: Springer Science and Business Media LLC

    DOI： 10.1007/s10751-021-01784-w 　

    ISSN： 0304-3843

    eISSN： 1572-9540

  10. High-speed rotating device for X-ray tomography with 10 ms temporal resolution Peer-reviewed

    Ryo Mashita, Wataru Yashiro, Daisuke Kaneko, Yasumasa Bito, Hiroyuki Kishimoto

    Journal of Synchrotron Radiation　28　(1)　322-326　2021/01/01

    Publisher: International Union of Crystallography (IUCr)

    DOI： 10.1107/s1600577520014666 　

    eISSN： 1600-5775

    More details Close

    The temporal resolution of X-ray tomography, using a synchrotron radiation X-ray source, has been improved to millisecond order in recent years. However, the sample must be rotated at a speed of more than a few thousand revolutions per minute, which makes it difficult to control the environment around the sample. In this study, a high-speed rotation device has been developed, comprising two synchronized coaxial motors movable along the direction of the axis, which can stretch or compress the rotating sample. Using this device, tomograms of breaking rubber were successfully obtained at a temporal resolution of 10 ms.

  11. Effect of silica nanoparticle filler on microscopic polymer α-relaxation dynamics Peer-reviewed

    Makina Saito, Ryo Mashita, Hiroyuki Kishimoto, Ryo Masuda, Yoshitaka Yoda, Makoto Seto

    Hyperfine Interactions　238　(1)　2017/11/27

    Publisher: Springer Science and Business Media LLC

    DOI： 10.1007/s10751-017-1466-y 　

    ISSN： 0304-3843

    eISSN： 1572-9540

  12. Quasielastic neutron scattering study of microscopic dynamics in polybutadiene reinforced with an unsaturated carboxylate Peer-reviewed

    Ryo Mashita, Rintaro Inoue, Taiki Tominaga, Kaoru Shibata, Hiroyuki Kishimoto, Toshiji Kanaya

    Soft Matter　13　(43)　7862-7869　2017

    Publisher: Royal Society of Chemistry (RSC)

    DOI： 10.1039/c7sm01262d 　

    ISSN： 1744-683X

    eISSN： 1744-6848

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    <p>The dynamics of BR is heterogeneous in ZDA/BR and a rigid network-like structure is responsible for its high elastic modulus.</p>

  13. Contrast variation by dynamic nuclear polarization and time-of-flight small-angle neutron scattering. I. Application to industrial multi-component nanocomposites Peer-reviewed

    Yohei Noda, Satoshi Koizumi, Tomomi Masui, Ryo Mashita, Hiroyuki Kishimoto, Daisuke Yamaguchi, Takayuki Kumada, Shin-ichi Takata, Kazuki Ohishi, Jun-ichi Suzuki

    Journal of Applied Crystallography　49　(6)　2036-2045　2016/11/08

    Publisher: International Union of Crystallography (IUCr)

    DOI： 10.1107/s1600576716016472 　

    eISSN： 1600-5767

    More details Close

    Dynamic nuclear polarization (DNP) at low temperature (1.2 K) and high magnetic field (3.3 T) was applied to a contrast variation study in small-angle neutron scattering (SANS) focusing on industrial rubber materials. By varying the scattering contrast by DNP, time-of-flight SANS profiles were obtained at the pulsed neutron source of the Japan Proton Accelerator Research Complex (J-PARC). The concentration of a small organic molecule, (2,2,6,6-tetramethylpiperidine-1-yl)oxy (TEMPO), was carefully controlled by a doping method using vapour sorption into the rubber specimens. With the assistance of microwave irradiation (94 GHz), almost full polarization of the paramagnetic electronic spin of TEMPO was transferred to the spin state of hydrogen (protons) in the rubber materials to obtain a high proton spin polarization (P H). The following samples were prepared: (i) a binary mixture of styrene–butadiene random copolymer (SBR) with silica particles (SBR/SP); and (ii) a ternary mixture of SBR with silica and carbon black particles (SBR/SP/CP). For the binary mixture (SBR/SP), the intensity of SANS significantly increased or decreased while keeping its q dependence for P H = −35% or P H = 40%, respectively. The q behaviour of SANS for the SBR/SP mixture can be reproduced using the form factor of a spherical particle. The intensity at low q (∼0.01 Å−1) varied as a quadratic function of P H and indicated a minimum value at P H = 30%, which can be explained by the scattering contrast between SP and SBR. The scattering intensity at high q (∼0.3 Å−1) decreased with increasing P H, which is attributed to the incoherent scattering from hydrogen. For the ternary mixture (SBR/SP/CP), the q behaviour of SANS was varied by changing P H. At P H = −35%, the scattering maxima originating from the form factor of SP prevailed, whereas at P H = 29% and P H = 38%, the scattering maxima disappeared. After decomposition of the total SANS according to inverse matrix calculations, the partial scattering functions were obtained. The partial scattering function obtained for SP was well reproduced by a spherical form factor and matched the SANS profile for the SBR/SP mixture. The partial scattering function for CP exhibited surface fractal behaviour according to q −3.6, which is consistent with the results for the SBR/CP mixture.

  14. Dynamics of polybutadiene reinforced with unsaturated carboxylate studied by muon spin relaxation (μSR) Peer-reviewed

    Ryo Mashita, Hiroyuki Kishimoto, Rintaro Inoue, Akihiro Koda, Ryosuke Kadono, Toshiji Kanaya

    Polymer　105　510-515　2016/11

    Publisher: Elsevier BV

    DOI： 10.1016/j.polymer.2016.07.050 　

    ISSN： 0032-3861

  15. Structure analyses of polybutadiene rubber crosslinked with unsaturated carboxylate using contrast variation small-angle neutron scattering Peer-reviewed

    Ryo Mashita, Hiroyuki Kishimoto, Rintaro Inoue, Toshiji Kanaya

    Polymer Journal　48　(3)　239-245　2015/10/28

    Publisher: Springer Science and Business Media LLC

    DOI： 10.1038/pj.2015.102 　

    ISSN： 0032-3896

    eISSN： 1349-0540

  16. Small-angle X-ray and neutron scattering analyses of highly crosslinked rubber with unsaturated carboxylic acid Peer-reviewed

    Ryo Mashita, Hiroyuki Kishimoto, Rintaro Inoue, Toshiji Kanaya

    Polymer Journal　45　(1)　57-63　2012/11/21

    Publisher: Springer Science and Business Media LLC

    DOI： 10.1038/pj.2012.200 　

    ISSN： 0032-3896

    eISSN： 1349-0540

  17. Dynamics of Stimulus Response of Swollen Nematic Elastomers Peer-reviewed

    Kenji Urayama, Ryo Mashita, Atsushi Fukunaga, Toshikazu Takigawa

    Progress of Theoretical Physics Supplement　175　103-109　2008

    Publisher: Oxford University Press (OUP)

    DOI： 10.1143/ptps.175.103 　

    ISSN： 0375-9687

  18. Loading effect on swelling of nematic elastomers Peer-reviewed

    Kenji Urayama, Ryo Mashita, Ichiro Kobayashi, Toshikazu Takigawa

    The Journal of Chemical Physics　127　(14)　2007/10/10

    Publisher: AIP Publishing

    DOI： 10.1063/1.2794333 　

    ISSN： 0021-9606

    eISSN： 1089-7690

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    Externally imposed loading has substantially different effects on the swelling of nematic elastomers in the high-temperature isotropic and low-temperature nematic states. In the isotropic state, the stretching drives a considerably large degree of further swelling, whereas the stretching-induced volume change in the nematic state is significantly suppressed. In the isotropic phase that favors the less anisotropic state, the further swelling occurs to reduce the shape anisotropy caused by the imposed elongation. In the nematic phase, no significant swelling is induced because further swelling decreases the nematic order enhanced by the applied stretching. These different loading effects in the isotropic and nematic states observed in the experiments are qualitatively described by a mean field theory.

  19. Stretching-Induced Director Rotation in Thin Films of Liquid Crystal Elastomers with Homeotropic Alignment Peer-reviewed

    Kenji Urayama, Ryo Mashita, Ichiro Kobayashi, Toshikazu Takigawa

    Macromolecules　40　(21)　7665-7670　2007/09/12

    Publisher: American Chemical Society (ACS)

    DOI： 10.1021/ma071104y 　

    ISSN： 0024-9297

    eISSN： 1520-5835

  20. Swelling and Shrinking Dynamics of Nematic Elastomers Having Global Director Orientation Peer-reviewed

    Kenji Urayama, Ryo Mashita, Yuko O. Arai, Toshikazu Takigawa

    Macromolecules　39　(24)　8511-8516　2006/11/01

    Publisher: American Chemical Society (ACS)

    DOI： 10.1021/ma061507i 　

    ISSN： 0024-9297

    eISSN： 1520-5835

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Misc. 8

  1. 放射光メスバウアーガンマ線を用いた準弾性散乱測 定系群が解明するゴムの原子・分子のダイナミクス Invited

    齋藤真器名, 間下亮

    日本放射光学会誌　38　(3)　207-215　2025/05

  2. Discovery of anisotropy in Johari–Goldstein-β process of stretched crosslinked polybutadiene by time-domain interferometry

    Ryo Mashita, Makina Saito

    SPring-8/SACLA Research Frontiers 2024　98-99　2025

  3. 4次元X線CT法によるフィラー充填ゴムの破壊現象の観察

    間下亮, 岸本浩通, 矢代航

    放射光学会誌　37　(5)　281-286　2024/09

  4. 先端実験施設のビッグデータ解析における展望

    間下亮, 増井友美, 岸本浩通

    高分子学会誌　73　331-333　2024/07

  5. 高機能タイヤ用ゴム材料開発に向けたXFELへの期待

    間下亮, 岸本浩通

    月刊OPTRONICS　2020/04

  6. コントラスト変調小角中性子散乱法による共架橋ゴムの構造解析

    間下亮, 岸本浩通, 井上倫太郎, 金谷利治

    日本中性子科学会誌「波紋」　28　(2)　84-88　2018/05

  7. 準弾性中性子散乱法による共架橋ゴムのダイナミクス解析

    井上倫太郎, 間下亮, 金谷利治

    中性子産業利用推進協議会 季報「四季」　37　2017/12

  8. 4 次元CT 法を用いたタイヤゴムの路面凹凸に対する変形挙動の観察 Invited

    間下亮, 岸本浩通

    Ⅹ線結像光学ニューズレター　40　1-3　2014/10

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Books and Other Publications 2

  1. 持続可能な社会を支えるゴム・エラストマー : 新素材・自己修復・強靱化と最先端評価技術

    間下亮

    化学同人　2023/03

    ISBN: 9784759814064

  2. Synchrotron Radiation-Based Quasi-Elastic Scattering Using Mössbauer Gamma Ray with neV-Energy Resolution

    Makina Saito, Toshiji Kanaya, Ryo Mashita

    IntechOpen　2019/09

Presentations 25

  1. 材料の“見えない”を可視化する WAVEBASE ー放射光×AI解析ー Invited

    間下亮

    人とくるまのテクノロジー展NAGOYA 特別技術講演　2026/06/17

  2. X線CT法を用いたゴムの破壊現象観察とその応用 Invited

    間下亮

    第67回ナノ構造ポリマー研究会　2026/03/12

  3. 産業応用に向けた時間領域干渉計によるポリマーダイナミクスの微視的理解

    間下亮

    第19回 核共鳴散乱研究会　2026/03/06

  4. 放射光・中性子を用いたゴムの静的および動的構造解析 Invited

    間下亮

    第304回ゴム技術シンポジウム　2025/06/16

  5. 放射光・中性子を活用したポリマーダイナミクスの微視的観察 Invited

    間下亮

    第3回量子ビームを用いた構造材料研究会　2025/05/30

  6. 時間領域干渉計を用いたガンマ線準弾性散乱法による ポリマーダイナミクスの微視的観察

    間下亮, 齋藤真器名, 依田芳卓, 永澤延元, 尾藤容正, 菊地龍弥, 岸本浩通, 瀬戸誠, 金谷利治

    第38回日本放射光学会年会・放射光科学合同シンポジウム　2025/01/12

  7. Quasi-elastic scattering study on α process under stretching in crosslinked rubber filled with silica by Mössbauer time-domain interferometry Invited

    Ryo Mashita, Makina Saito, Yoshitaka Yoda, Nobumoto Nagasawa, Yasumasa Bito, Hiroyuki Kishimoto, Makoto Seto, Toshiji Kanaya

    International Symposium on the Industrial Applications of the Mössbauer Effect 2024　2024/09/04

  8. 「2023年度 第20回SPring-8産業利用報告会 最優秀発表賞 講演」X線4次元CT法を用いたタイヤゴム材料の破壊過程の観察 Invited

    間下亮

    SPring-8利用推進協議会 2024年度 総会　2024/04/12

  9. タイヤゴム材料の破壊過程の観察 Invited

    間下亮, 岸本浩通

    SPRUC 3研究会合同研究会　2024/03/29

  10. X線4次元CT法を用いたタイヤゴム材料の破壊過程の観察 Invited

    間下亮, 岸本浩通

    第20回SPring-8産業利用報告会　2023/09/07

  11. 4次元X線CT法で見たゴムの破壊現象 Invited

    間下亮, 岸本浩通, 矢代航

    Society of Plastics Engineers, Inc.日本支部講演会　2021/10/15

  12. 中性子を用いたゴムの局所ダイナミクス Invited

    間下亮

    第68回高分子討論会　2019/09/27

  13. 高機能タイヤ用ゴム材料開発へのXFEL検討 Invited

    増井友美, 金子房恵, 柴田祐介, 岸本浩通, 井上伊知, 大坂泰斗, 矢橋牧名, 登野健介

    SPring-8シンポジウム　2019/08/31

  14. ガンマ線準弾性散乱法を用いた架橋ゴムのダイナミクス Invited

    間下亮, 齋藤真器名

    SPRUC 不規則系物質先端科学研究会　2019/02/23

  15. 中性子の産業利用 Invited

    間下亮

    平成30 年度中性子実験技術基礎講習会（レベル１講習会）　2018/11/02

  16. 中性子準弾性散乱法を用いたゴム中における シリカ表面状態とダイナミクスの関係 Invited

    間下亮, 岸本浩通, 菊地龍弥, 金谷利治

    平成30 年度J-PARC MLF 産業利用報告会　2018/07/23

  17. 中性子の産業利用 Invited

    間下亮

    平成29年度中性子実験技術基礎講習会（レベル１講習会）　2017/11/28

  18. 中性子を用いたゴムのダイナミクス研究 Invited

    間下亮

    平成29年度ソフトマター中性子散乱研究会　2017/11/27

  19. Study on static and dynamic structure of tire rubber by using synchrotron radiation X-ray and Neutron. Invited

    Ryo Mashita

    2017/11/20

  20. 4次元X線CT法で見えた ゴムの新たな変形挙動 Invited

    間下亮, 増井友美, 岸本浩通

    第30回日本放射光学会年会　2017/01/09

  21. ミュオンスピン緩和法を用いた共架橋ゴムのダイナミクス解析 Invited

    間下亮, 岸本浩通, 井上倫太郎, 金谷利治

    量子ビームによるゴムの構造とダイナミクス研究会　2016/07/08

  22. 中性子・ミュオンを用いた共架橋ゴムの静的構造とダイナミクス研究

    間下亮, 井上倫太郎, 金谷利治

    2014年日本中性子科学会年会　2014/12/10

  23. Studies on Dynamcs of Highly Crosslinked Rubber by mSR

    間下亮, 井上倫太郎, 高橋伸明, 金谷利治

    第5回J-PARC/MUSE成果報告会　2014/05/26

  24. 4次元CT法を用いたタイヤゴムの変形挙動観察 Invited

    間下亮, 岸本浩通

    X線ナノ集光技術研究会　2013/11/17

  25. X線・中性子を用いた共架橋高分子の分子構造解析

    間下亮, 岸本浩通, 井上倫太郎, 金谷利治

    第61回高分子討論会　2012/09/19

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Research Projects 1

  1. 非平衡系MIスキームによる未来材料開発期間の劇的短縮

    間下亮, 矢代航, 小川紘樹

    Offer Organization: 新エネルギー・産業技術総合開発機構（NEDO）

    System: NEDO先導研究プログラム 新技術先導研究プログラム

    2023/05 - 2026/03