超分子ポリメリゼーションと金属有機多面体の凝結の空間時間制御

Alexandre Legrand¹, Li-Hao Liu², Philipp Royla³

¹Institute for Integrated Cell-Material Sciences, Kyoto University, Yoshida, Sakyo-ku, Kyoto 606-8501, Japan.

Journal of the American Chemical Society

|March 1, 2021

まとめ

研究者は光と酸を用いて金属有機多面体 (MOP) ゲルの空間時間制御を達成しました. この画期的な技術により繊細な柔らかい材料の精密な形状とパターンが実現できます

科学分野:

超分子化学
材料科学
柔らかい物質の物理

背景:

時間と空間の両方でメタロゲルのような協調性ベースの超分子材料の組み立てを制御することは困難です.
金属有機多面体 (MOP) は安定した多孔性を提供しますが,制御された組立方法が必要です.

研究の目的:

MOPベースの柔らかい材料の組み立てを空間時間的に制御する方法を開発する.
凝固形成と特性に対する酸濃度の影響を調査する.
パターンの形成のために,光誘発された,局所的ゲル形成を示すために.

主な方法:

MOP溶液からゲル形成を誘発する化学的刺激剤としてトリフオロアセチン酸 (TFA) を利用した.
時間分解のダイナミック光散射,UV-VIS吸収,および1H NMRスペクトロスコーピーを用いて,アセンブリ運動を監視した.
結果となるゲルの機械的性質を特徴付けるために,レオロギー測定を用いた.
局所ゲルアセンブリのための光酸生成器 (ピラニン) と光照射が組み込まれています.

主要な成果:

酸の濃度はゲル形成の動態,クロスリンクの密度,粒子の大きさ,ネットワークの密度を左右する.
酸の濃度が上昇すると,MOPゲルの柔らかさと硬さが低下する.
ピラニンの光照射は,MOPゲルの自己組み立てを正確に局所的に誘発します.
この光誘発方法を使って,MOPゲルを望ましい形状にパターニングする能力を示しました.

結論:

MOPベースの柔らかい材料の同時時間的および空間的な制御は,酸と光の刺激の組み合わせを使用して達成できます.
開発された方法は,多孔性MOPゲルの正確なパターニングを可能にします.
これらの発見は,MOP材料をセンシング,分離,触媒,および薬物投与装置に統合する可能性を開示しています.

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