Precise synthesis of semiconducting polymers based on condensative chain-growth polymerization including the trigger reaction through pi-conjugation

2020 Fiscal Year Final Research Report

• Project/Area Number: 19K22211
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 35:Polymers, organic materials, and related fields
• Research Institution: Yamagata University
• Principal Investigator: Higashihara Tomoya 山形大学, 大学院有機材料システム研究科, 教授 (50504528)
• Project Period (FY): 2019-06-28 – 2021-03-31
• Keywords: 半導体高分子 / 有機薄膜トランジスタ / 縮合的連鎖重合

Outline of Final Research Achievements

A new polycondensation method has been developed based on the aldol condensation reaction utilizing the intramolecular resonance effect of the anionic monomer through π-conjugation. Indeed, a novel AB type monomer was designed to synthesize the semiconducting poly(oxindolidene thienylene vinylene) (POTV). The polymerization readily proceeded initiated with 5-nitro-2-thiophenecarbaldehyde after the α-proton abstraction of the oxindole group by the reaction of the monomer precursor with lithium hexamethylsilazide (LiHMDS)/12-crown-4. As a result, the objective POTV with Mn = 5300 and PDI = 1.57 could be obtained with a good yield (65%). In addition, an organic field effect transistor (OFET) was based on POTV exhibited p-type characteristics, with a hole mobility of 2.24×10-4 cm2/V/s.

Free Research Field

高分子合成

Academic Significance and Societal Importance of the Research Achievements

本研究で開発した合成手法により得られるポリマー材料は、残存遷移金属およびハロゲンが本質的にゼロであるため、従来法で得られるポリマー材料よりも電荷輸送トラップが少なく、高い電荷移動度をもつ有機トランジスタへの応用が期待できる。また半導体高分子材料の分子量や分子量分布は、それら機能に多大な影響を及ぼすため、π共役系高分子の合成において、遷移金属・ハロゲンフリー系かつリビング重合系の方法論の確立は学術上大きな意義を有する。