Reversible Morphological Transformation between Polymer Nanocapsules and Thin Films through Dynamic Covalent Self-assembly

Jeehong Kim, Kangkyun Baek,* Dinesh Shetty, Narayanan Selvapalam, Gyeongwon Yun, Nam Hoon Kim, Young Ho Ko, Kyeng Min Park, Ilha Hwang, and Kimoon Kim*

Scheme 1 Formation of 2D polymer film 3 and polymer nanocapsule 2 through reversible disulfide bond formation and reversible morphological transformation between them.

We developed a facile method for synthesizing polymer nanocapsules and thin films using multiple in-plane stitching of monomers via the formation of reversible disulfide linkages. Due to the reversibility of the disulfide linkages, the nanostructured materials readily transform their structures in response to environmental changes at room temperature. For example, in reducing environments, the polymer nanocapsules release loaded cargo molecules. Moreover, reversible morphological transformations between these structures can be achieved by simple solvent exchanges. Our work presents a novel approach for the formation of robust nano/microstructured materials that dynamically respond to environmental stimuli.

티올 작용기가 도입된 쿠커비투[6]릴(CB[6])에 서로 다른 용매를 적용하여 각각 마이크로필름과 나노 캡슐의 고분자 구조체를 합성했고, 또한 용매에 따라 두 가지 구조체(마이크로필름, 나노 캡슐, 그림설명 참조)가 서로 변환할 수 있는 기술을 개발했다. 이러한 현상을 동적 광산란법(DLS) 및 주사전자현미경(SEM), 투과전자현미경(TEM), 적외선분광법(FT-IR), 원자 힘 현미경(AFM) 등을 이용하여 구조체의 합성 및 변환과정을 밝혔다. 이 연구 성과는 화학분야 권위지 안게반테 케미(Angewandte chemie, IF 11.336)誌 온라인에 1월 21일 게재됐다.