Aggregation Structure of Hyper-branched Block Copolymers in Solution

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K05184
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 35020:Polymer materials-related
• Research Institution: Kyoto University
• Principal Investigator: Tosaka Masatoshi 京都大学, 化学研究所, 准教授 (10273509)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 多分岐高分子 / 構造制御 / 凝集構造 / シミュレーション / 自己組織化 / 表面力測定

Outline of Final Research Achievements

The formation process of hyperbranched polymers (HBPs) synthesized in one step by our method was simulated. Subsequent analysis of statistical trends in molecular weight and number of branches show that the products are obtained as designed. We grew hydrophobic polymers with controlled branching structure from linear hydrophilic polymers, and experimentally demonstrated that the branching structure can be used to control the morphology of the aggregation structure from the morphological change of the micelles obtained. As for the aggregation state on the substrate surface, surface force measurements were performed by sandwiching HBP solution between small gaps, and the "hard wall distance" at which stress rises sharply was about twice as large for HBP as for linear polymers.　Dynamic viscoelasticity measurements showed a decrease in viscosity due to the introduction of branching and the interaction of the end blocks.

Free Research Field

高分子物理

Academic Significance and Societal Importance of the Research Achievements

我々の開発した新しいHBP合成法が、ほぼ設計通りに構造を制御する有用な方法であることを示した。この方法で合成した多分岐ブロックコポリマー（HBBCP）がミセルなどを自己組織化する際、分岐がどの様な効果を及ぼすかについて定量的な理解を進展させた。また、新規な形状のベシクルが形成される事を見出し、有効な薬剤単体としての可能性が見出された。さらに、HBPが境界潤滑での摩擦提言に有効であると示された。エマルジョン重合をHBBCP合成に適用することで、効率的合成を可能とした。