Rheo-optical study on internal filler structures in rubber composites with terahertz polarization spectroscopy

2020 Fiscal Year Final Research Report

• Project/Area Number: 18H01190
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 13040:Biophysics, chemical physics and soft matter physics-related
• Research Institution: Keio University
• Principal Investigator: Okano Makoto 慶應義塾大学, 理工学部(矢上), 講師 (10612525)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Keywords: テラヘルツ偏光計測 / 流動光学 / ゴム複合材料 / テラヘルツ光弾性

Outline of Final Research Achievements

We studied the relationship between carbon black fillers and host rubber matrices in a carbon-black-rubber composite, which is one of the typical polymer composites, with a spatio-temporal resolved terahertz polarization spectroscopy. We focus on the investigation of change in internal filler structures during two characteristic dynamical mechanical responses, i.e., the stress relaxation and the stress softening. Through the development of high-speed, high precision terahertz polarimeter and the spectral analysis based on a combination of Monte-Carlo simulation and effective medium theory, we systematically revealed the change in internal filler structures due to the mechanical responses. Our findings would provide a new perspective for the investigation of the relationship between the fillers and rubber molecules in the black rubbers during dynamical, mechanical responses.

Free Research Field

光物性物理学

Academic Significance and Societal Importance of the Research Achievements

カーボンブラックフィラー添加ゴムは我々の日常生活に欠かせない物質であるが、その内部状態については未解明な点も残っている。本研究では、内部フィラー構造を敏感に検出できるテラヘルツ光に着目し、マクロな力学応答にともなうミクロな内部フィラー構造の変化を実験的に観測することに成功した。本研究のマクロな特性からミクロな構造を推定するというアプローチは、ミクロな構造の観察からマクロな力学応答を推定する従来の方法とは大きく異なるため、従来の方法に対して相補的な情報を与えることが期待できる。