Understanding the Mechanism of Flower Petal Transparency Change and Their Applications for Biomimetics

2023 Fiscal Year Final Research Report

• Project/Area Number: 19K05620
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 35020:Polymer materials-related
• Research Institution: Chitose Institute of Science and Technology
• Principal Investigator: Karthaus Olaf 公立千歳科学技術大学, 理工学部, 教授 (80261353)
• Co-Investigator(Kenkyū-buntansha): 谷尾 宣久 公立千歳科学技術大学, 理工学部, 教授 (50217121)
• Project Period (FY): 2019-04-01 – 2024-03-31
• Keywords: biomimetics / flower petals / transparency / films

Outline of Final Research Achievements

The internal structure of flower petals was investigated by optical and electron micrsocopy and we found that air-filled voids are responsible for the white color of the petals by strong light scattering. We were able to fill these voids with liquids and gels that led to a change in opacity - the petals became transparent. As a biomimetic analogue we were able to produce porous films of a fluorinated polymer that showed the same change in transparency when dry and wet. In this case, the change was reversible, while in the petal case, it was not.

Free Research Field

Polymer Science

Academic Significance and Societal Importance of the Research Achievements

Biomimetics can produce functional materials by environmentally friendly processes that are energy-saving. The transparency change of films without any external triggers offers new applications in remote areas and can be used for automatic shading of windows or as sensors.