Development of new methods for measuring small displacements of interfaces to enable local interfacial tension measurements at flexible interfaces

2020 Fiscal Year Final Research Report

• Project/Area Number: 17H03078
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Analytical chemistry
• Research Institution: Osaka University
• Principal Investigator: Tsukahara Satoshi 大阪大学, 理学研究科, 教授 (50207338)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: 表面・界面物性 / 界面張力 / 強制振動 / 界面微小振動

Outline of Final Research Achievements

The purpose of this study is to determine the surface tensions of liquids of various physical properties by measuring their surface oscillations in a circular container of a constant size.
In this study, intermittent airflow, alternative-current magnetic field, and vibration using piezoelectric devices were employed as excitation methods for the liquid surface oscillation. As a result, it was found that all of these methods were able to induce effective forced oscillation on the liquid surfaces. Detailed analysis showed that the resonance frequencies obtained by all methods were independent of the excitation methods. This fact proves that all the measurements reflect the unique properties of the liquid surface (i.e. surface tension).

Free Research Field

分析化学，界面化学，コロイド化学

Academic Significance and Societal Importance of the Research Achievements

フレキシブルな界面は，世の中に数多く存在する。日々用いる水の表面や，洗剤による洗濯にも関係する。ドレッシングやマヨネーズなどの食品にも界面は存在するし，化粧品のクリーム等にも多くの界面活性剤が用いられている。医薬品を目的の器官まで届けるドラッグデリバリーシステムにおいても，医薬品を取り囲んでいる界面活性剤が重要な役割を果たしている。このような界面すべてに界面張力が関与しており，本研究の波及効果は計り知れない。
なお，本研究の方法を用いれば，極めて小さな大きさ（数十μm）の極微小界面の界面張力でも原理的に測定可能であるため，極めて高価な試料でも有効な測定が可能である。