Mechanical Toughening and Acceleration of Stimulus Responsiveness of Soft Materials via Densely Packing of Microgels

• Project/Area Number: 18K19113
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 35:Polymers, organic materials, and related fields
• Research Institution: Kyoto Institute of Technology
• Principal Investigator: Urayama Kenji 京都工芸繊維大学, 材料化学系, 教授 (20263147)
• Co-Investigator(Kenkyū-buntansha): 鈴木 大介 信州大学, 学術研究院繊維学系, 准教授 (90547019)
• Project Period (FY): 2018-06-29 – 2021-03-31
• Project Status: Completed (Fiscal Year 2020)
• Budget Amount: ¥6,240,000 (Direct Cost: ¥4,800,000、Indirect Cost: ¥1,440,000); Fiscal Year 2019: ¥3,120,000 (Direct Cost: ¥2,400,000、Indirect Cost: ¥720,000); Fiscal Year 2018: ¥3,120,000 (Direct Cost: ¥2,400,000、Indirect Cost: ¥720,000)
• Keywords: 高分子ゲル / ゲル微粒子 / コンポジットゲル / 高分子レオロジー / 高分子力学物性 / ゲル / 温度応答性 / 微粒子 / ペースト / 力学 / レオロジー

Outline of Final Research Achievements

Gel composites in which the microgels are densely packed are prepared. We confirmed the significant mechanical toughening via densely packing of microgels. The gel composites exhibit a volume change in response to temperature change which results from the thermo-responsiveness of the microgels. Characteristically, the gel composites do not form the hard skin layer in the initial stage of the shrinking process, while the corresponding bulk thermo-responsive gels do.

Academic Significance and Societal Importance of the Research Achievements

ゲル微粒子をゲルに内包させたコンポジットゲルは過去に報告されているが，その充填率は高々40%程度であった。本研究は，微粒子どうしの接触によって変形するほど超高密充填したコンポジットゲルを創成した。超高密充填により，既往研究では見られていなかった顕著な力学補強効果と温度応答性の特異性を見出した。

Research Products

• [Journal Article] Two-step yielding behavior of densely packed microgel mixtures with chemically dissimilar surfaces and largely different sizes (2020)
  • Author(s): Saori Minami, Takumi Watanabe, Yuma Sasaki, Haruka Minato, Atsushi Yamamoto, Daisuke Suzuki, Kenji Urayama
  • Journal Title: Soft Matter Volume: 16 Issue: 31 Pages: 7400-7413
  • DOI: 10.1039/d0sm00366b
  • Peer Reviewed
• [Journal Article] Criteria for colloidal gelation of thermo-sensitive poly(N-isopropylacrylamide) based microgels (2020)
  • Author(s): Minami Saori、Yamamoto Atsushi、Oura Shun、Watanabe Takumi、Suzuki Daisuke、Urayama Kenji
  • Journal Title: Journal of Colloid and Interface Science Volume: 568 Pages: 165-175
  • DOI: 10.1016/j.jcis.2020.02.047
  • Peer Reviewed
• [Journal Article] Rheological Aspects of Colloidal Gels: Formation, Structure, Linear and Nonlinear Viscoelasticity (2019)
  • Author(s): Minami, S., Suzuki, D., Urayama, K.
  • Journal Title: Current Opinion in Colloid and Interface Science Volume: 43 Pages: 113-124
  • DOI: 10.1016/j.cocis.2019.04.004
  • Peer Reviewed
• [Journal Article] Viscoelasticity of Dense Suspensions of Thermosensitive Microgel Mixtures Undergoing Colloidal Gelation (2018)
  • Author(s): Minami, S., Watanabe, T., Suzuki, D., Urayama, K.
  • Journal Title: Soft Matter Volume: 14 Issue: 9 Pages: 1596-1607
  • DOI: 10.1039/c7sm02411h
  • Peer Reviewed
• [Journal Article] Elastic and Flow Properties of Densely Packed Microgel Mixtures with Size- and Stiffness Disparities (2018)
  • Author(s): Nakaishi, A., Minami, S., Oura, S., Watanabe, T., Suzuki, D., Urayama, K.
  • Journal Title: Macromolecules Volume: 51 Issue: 23 Pages: 9901-9914
  • DOI: 10.1021/acs.macromol.8b01625
  • Peer Reviewed
• [Presentation] 感温性ゲル微粒子懸濁液が形成するコロイドゲルのレオロジー挙動 (2020)
  • Author(s): 山本敦史、南沙央理、大浦舜、渡邊拓巳、鈴木大介、浦山健治
  • Organizer: 日本レオロジー学会第47年会
• [Presentation] コロイドゲルを形成する温度応答性ゲル微粒子懸濁液の非線形レオロジー挙動 (2020)
  • Author(s): 山本敦史、乾拓海、鈴木大介、浦山健治
  • Organizer: 第13回西日本支部学生ワークショップ、日本レオロジー学会西日本支部
• [Presentation] 温度応答性ゲル微粒子ペーストのレオロジー (2019)
  • Author(s): 浦山健治
  • Organizer: 第21回サイコレオロジー研究会
  • Invited
• [Presentation] 温度応答性ゲル微粒子ペーストのレオロジー (2019)
  • Author(s): 浦山健治
  • Organizer: 日本レオロジー学会サイコレオロジー研究会
  • Invited