The development spectroscopic method to observe 2D viscoelasticity of liquid surface with EMS system

2018 Fiscal Year Final Research Report

• Project/Area Number: 15K04722
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: General applied physics
• Research Institution: Tokyo Denki University
• Principal Investigator: HOSODA Maiko 東京電機大学, 理工学部, 准教授 (40366406)
• Project Period (FY): 2015-04-01 – 2019-03-31
• Keywords: 粘性 / 2次元粘弾性

Outline of Final Research Achievements

Langmuir films adsorbed on liquid surfaces have attracted a great interest as the real evidence of the mono-molecular layer, which show the phase transition and critical behavior in two-dimensional system as seen in usual bulk materials. However, accurate measurements of these surface properties have been difficult, since the mechanical effect of the adsorbed mono-molecular films is easily hidden by the huge contribution of the bulk properties, such as bulk viscosity and elasticity. Recently, we succeeded in developing the new methodology of the rheology measurement with uniquely developed principle of the electro magnetically driving system. In our system, we can continuously observe the mechanical properties after once a small floating prove is set on the liquid surface. The surface viscosity could be successfully determined as a function of the concentration.

Free Research Field

機能性レオロジー

Academic Significance and Societal Importance of the Research Achievements

表面粘弾性計測の重要性は認識されてはいたが、分子単層膜の持つ粘弾性の寄与は非常に小さく、基板であるバルクの水の力学物性に埋もれてしまうことが測定を困難にしていた。本手法では遠隔でプローブにトルクを印加して実現される回転速度を計測するため、プローブの小型化が原理的に可能となり困難を克服した。今回の成果は、従来からの2 次元物質の物性物理を研究する上での重要な情報を提供するのみならず、近年特に産業応用上の大きな発展が見込まれるインクジェットやマイクロ流路などのミクロな液体デバイスの設計・製作においてもきわめて有意義な知識を提供することとなった。