What is the role of insulating polymers in conductive polymer diluted thin films?

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K14698
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 35030:Organic functional materials-related
• Research Institution: National Institute of Advanced Industrial Science and Technology (2023); Tokyo University of Science (2021-2022)
• Principal Investigator: Sato Tomoya 国立研究開発法人産業技術総合研究所, エレクトロニクス・製造領域, 研究員 (80836370)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 導電性高分子 / 絶縁性高分子 / 構造変化 / 電荷輸送特性

Outline of Final Research Achievements

It has been reported that diluting conductive polymers with large amounts of insulating polymers reduces electron trapping in the conductive polymers and improves their electron transport properties. However, the role of insulating polymers in improving the electron transport properties of conducting polymers has not been clarified. In this study, the case of polyfluorene (PFO) and polystyrene (PS) blends was investigated. We clarified the role of PS in the structural change of PFO due to the blending of both polymers by investigating the dependence of the weight average molecular weight of PS in this study. We also found that there is a high correlation between the amount of structural change in PFO and the improvement in electron transport properties.

Free Research Field

有機エレクトロニクス

Academic Significance and Societal Importance of the Research Achievements

絶縁性高分子を利用した導電性高分子の希釈法は電荷輸送特性の改善に対して非常に有効な手法になる可能性を秘めているが、研究例が少ないため未解明な部分が多く残されていた。これに対して、本研究にて絶縁性高分子が担う役割を明らかにできたことは手法の確立に向け、学術的に非常に意義のある成果と言える。さらに、導電性高分子の構造変化量と電子輸送特性の改善との間に高い相関性も見出し、高分子ELの高性能化や素子設計につながる有用な知見が得られた。