Decarbonyrative reaction for mechanism study and synthetic applications of termination reaction in radical polymerization

2022 Fiscal Year Final Research Report

• Project/Area Number: 19K05593
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 35010:Polymer chemistry-related
• Research Institution: National Institute for Materials Science
• Principal Investigator: NAKAMURA Yasuyuki 国立研究開発法人物質・材料研究機構, 統合型材料開発・情報基盤部門, 主任研究員 (30456826)
• Project Period (FY): 2019-04-01 – 2023-03-31
• Keywords: ラジカル重合反応 / ラジカル反応 / 反応機構 / 停止反応 / 光反応 / カルボニル化合物 / 反応選択性 / 粘度

Outline of Final Research Achievements

The mechanism of the termination reaction in radical polymerization was investigated using photo-induced decarbonylative radical reaction of carbonyl compounds. The advantage of this reaction is the fact that the only byproduct, CO, does not affect the termination reaction. The efficient radical generation was confirmed for carbonyl compounds mimicking the propagating chain end structure. Importantly, decarbonylation reaction generated diffused radicals, which is suitable for the study of radical termination. Experiments of temperature and viscosity variations revealed the relationship between these condition factors and termination mechanism. The result was consistent with the mechanism we have proposed, and strongly suggested that this is the general mechanism of radical termination independent of radical precursors.

Free Research Field

高分子化学

Academic Significance and Societal Importance of the Research Achievements

ラジカル重合反応はプラスチックなど高分子の生産に広く用いられる合成反応である。本研究ではこの反応の要素の中でも最終的に高分子の分子構造を決定する重要な要素である重合停止反応の機構（反応の仕組み）の解明を、新規なカルボニル化合物の光反応を用いる手法にて行った。反応機構（反応の仕組み）について詳細な知識が得られたことは、ラジカル重合反応を利用した高分子合成の効率化や改善に貢献する。