| Project/Area Number |
19K23499
|
|---|
| Research Category |
Grant-in-Aid for Research Activity Start-up
|
| Allocation Type | Multi-year Fund |
|---|
| Review Section |
0301:Mechanics of materials, production engineering, design engineering, fluid engineering, thermal engineering, mechanical dynamics, robotics, aerospace engineering, marine and maritime engineering, and related fields
|
|---|
| Research Institution | Doshisha University |
|---|
Principal Investigator |
Hara Shumpei 同志社大学, 理工学部, 助教 (20844088)
|
|---|
| Project Period (FY) |
2019-08-30 – 2022-03-31
|
| Project Status |
Completed (Fiscal Year 2021)
|
| Budget Amount *help |
¥2,860,000 (Direct Cost: ¥2,200,000、Indirect Cost: ¥660,000)
Fiscal Year 2020: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000)
Fiscal Year 2019: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000)
|
|---|
| Keywords | 流動誘起ゲル / 乱流 / 界面活性剤 / 相転移 / 可逆・不可逆性 |
|---|
| Outline of Research at the Start |
ソフトマテリアルの安定生産及び流動誘起ゲル相転移現象を利用した新規高機能性材料の開発等に向け，流動誘起ゲル相転移の理論構築が必要とされる．本研究では，流動条件を変更しつつ実験を行い，解析結果から流動誘起ゲルの作製プロセスの構築を目的とする．流動誘起ゲル相転移の可逆・不可逆性を整理できるモデル式を提案し，形成されたゲルの構造とその力学的特性をそれぞれ検証することで，体系的にまとめ上げ，目的達成を目指す．従来研究では，マイクロ流路中の層流に現れる可逆的ゲルに着目したものがほとんどだが，本研究では，径の大きい流路内に現れる乱流に亘る幅広い流動条件下で，流動誘起ゲル相転移の可逆・不可逆性の調査を行う．
|
| Outline of Final Research Achievements |
The conditions for reversible and irreversible phase transitions and mechanical properties of flow-induced gels formed by dosing devices with various filters were evaluated by visualization experiments, dynamic viscoelasticity measurements using a rheometer, particle image velocimetry, and planar laser-induced fluorescence. Flow-induced gels are formed in an adequate condition of a adequate deformation rate and deformation amount, even in solutions with low concentrations on the order of tens of ppm. The difference between reversible and irreversible phase transitions was found to appear in the standard deviation of the storage modulus and loss modulus in the low-frequency range. It was also found that the flow-induced gel formed in turbulent flow swells to a size two orders of magnitude larger than that of the surrounding fluid by turbulent diffusion.
|
| Academic Significance and Societal Importance of the Research Achievements |
流動誘起ゲルの理論構築はソフトマテリアルの安定生産及び相転移現象を利用した新技術・次世代の新規高機能性材料の開発に繋がる．流動誘起ゲル相転移の具体的事例が少ないこともあり，その可逆・不可逆相転移の条件や力学的特性など未解明な部分が多い．本研究は相転移の可逆・不可逆性を整理しつつ，力学的特性まで含めた流動誘起ゲルの作製プロセスを構築した．この知見は，ゾル-ゲル相転移に関する研究の進展に大きく寄与するものであり，今後はさらに汎用性の高いゲル形成条件の予測式の提案に向けた重要な知見となる．
|
