Effect of liquid flow on the forces and physical properties of surfaces in liquids

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K05264
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 29020:Thin film/surface and interfacial physical properties-related
• Research Institution: Shinshu University
• Principal Investigator: McNamee Cathy 信州大学, 学術研究院繊維学系, 教授 (40504551)
• Co-Investigator(Kenkyū-buntansha): 小川 智之 東北大学, 工学研究科, 准教授 (50372305)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: フォース測定 / 液体の流れ / 相互作用

Outline of Final Research Achievements

Many systems require particles or soft matter that are dispersed in liquids to flow through confined areas. Surface forces are well understood when the liquid contains no flow. However, it is unclear how a flow in a liquid affects surface forces. In this study, we used a combined Atomic Force Microscope-peristaltic pump system to determine how a flow in the liquid between two surfaces affects the forces of a system. We studied (1) the effect of the surfactant charge and concentration on the change in the forces between two charged surfaces in surfactant solutions by a liquid flow, (2) the effect of surface roughness on the change in the surface forces between two charged surfaces by a liquid flow, and (3) the effect of flow on surfaces stabilized by polymers. The results of this study will improve the performance of nano-technological or biological systems that require the movement of particles or soft matter through confined areas, e.g. ink-jet printing.

Free Research Field

コロイド・界面化学

Academic Significance and Societal Importance of the Research Achievements

液体に分散した粒子やソフトマターが狭い領域を流れる状況は実世界でよくみられるが、液体の流れが表面力にどのように影響するかは不明である。身の回りで一般的な系である（1）液体中の界面活性剤、（2）粗い表面、および（3）ポリマーについて、液流が表面力にどのように影響するかを評価した。その結果、液流が表面力に与える影響は系に依存することが分かった。本研究の結果は、狭い領域を通る粒子やソフトマター制御を必要とするナノテクノロジーや生物学的システムのパフォーマンスを改善すると期待できる。