Meso-scale liquid crystal/polymer phase separation with anisotropic and hierarchical nonuniform structures and development of thermoresponsive light control devices

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K03779
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 13040:Biophysics, chemical physics and soft matter physics-related
• Research Institution: National Institute of Advanced Industrial Science and Technology
• Principal Investigator: Kakiuchida Hiroshi 国立研究開発法人産業技術総合研究所, 材料・化学領域, 主任研究員 (40343660)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 高分子ネットワーク液晶 / 光重合誘起相分離 / ネマチック等方相転移 / 分子配向秩序 / 不均一露光 / スマートウィンドウ / 刺激応答性 / 偏光選択性

Outline of Final Research Achievements

There are no reports of positive and precise control of polymer network liquid crystals (PNLC) from the viewpoint of photo-exposure through photopolymerization-induced phase separation (PPIPS). This is mainly because PPIPS is a self-organizing process and is not easy to control. In this research, we have actively controlled PPIPS with the technique of non-uniform exposure and have worked on the development of higher-order optical structures. Specifically, with this exposure technology, we developed (1) thermoresponsive PNLCs that can create forward- and reverse-mode thermoresponsive transmittance control, (2) anisotropic phase-separation structured PNLCs, and (3) thermoresponsive PNLCs with hemispheric transmission controllability, and we elucidated (4) the thermal behavior of liquid crystals and reactive mesogens at different stages during PPIPS.

Free Research Field

光機能性材料

Academic Significance and Societal Importance of the Research Achievements

本研究では、光重合誘起相分離(PPIPS)を通して形成される高分子ネットワーク液晶(PNLC)の光学構造を不均一露光の手法で積極的に制御し、従来にない構造と機能をもった光波制御素子を作製した。これは作製技術と機能素子創製の二つの点で意義がある。作製の観点では、本知見はPPIPS技術の可能性を拡げ、他の材料系でも展開することが期待される。機能素子の創製では、実用的な刺激応答性の光波制御特性を持たせたことにより、スマートウィンドウや刺激応答型の偏光素子など、様々な応用展開の可能性を示した。