Elucidation of Fundamental Properties of the Longest Bottlebrush Polymer and Its Application to Innovative Materials

2022 Fiscal Year Final Research Report

• Project/Area Number: 20H02454
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 26030:Composite materials and interfaces-related
• Research Institution: National Institute for Materials Science
• Principal Investigator: Yamauchi Yoshihiro 国立研究開発法人物質・材料研究機構, 機能性材料研究拠点, 独立研究者 (60709343)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: ボトルブラシポリマー / リビング重合 / 開環オレフィンメタセシス重合 / 原子移動ラジカル重合

Outline of Final Research Achievements

The synthesis of the longest bottlebrush polymers reported so far, reaching up to 7 μm in length, was achieved through a two-step process using a norbornene derivative containing two 2-bromoisobutylate functional groups (NB). The excellent reactivity of NB in ring-opening metathesis polymerization played a crucial role in this achievement, allowing for well-controlled polymerization with near-complete conversion of NB even at monomer-initiator ratios as high as 10,000. The resulting polymer obtained from NB was subsequently transformed into various bottlebrush polymers through a divergent synthetic pathway by grafting vinyl monomers onto the 2-bromoisobutylate units using atom transfer radical polymerization. The structure of these ultra-long bottlebrush polymers was directly visualized using atomic force microscopy.

Free Research Field

高分子化学

Academic Significance and Societal Importance of the Research Achievements

ボトルブラシポリマーは、『長さ』と『直径』の制御可能な１次元マテリアルと見なすことができる。１次元マテリアルは、その普遍的重要性を反映し、様々な長さと直径を持つ１次元マテリアルが長年にわたり研究されており、ある種の１次元マテリアルは高分子材料と組み合わせることで、軽量かつ強度の高い複合材料としても利用される。ボトルブラシポリマーの合成の適用範囲を拡大することは、高分子化学の発展、及び１次元マテリアルに関連する材料科学の発展に繋がることが期待される。