Mechanochemistry of an Interlocked Poly[2]catenane:From Single Molecule to Bulk Gel  

作　　者：Hao Xing Zhandong Li Wenbo Wang Peiren Liu Junkai Liu Yu Song Zi Liang Wu Wenke Zhang Feihe Huang 

机构地区：[1]State Key Laboratory of Chemical Engineering,Department of Chemistry,Center for Chemistry of High-Performance&Novel Materials,Zhejiang University,Hangzhou 310027(China) [2]State Key Laboratory of Supramolecular Structure and Materials,College of Chemistry,Jilin University,Changchun 130012(China) [3]Key Laboratory of Macromolecular Synthesis and Functionalization of Ministry of Education,Department of Polymer Science and Engineering,Zhejiang University,Hangzhou 310027(China) [4]Department of Chemistry,The Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction,Institute for Advanced Study,Department of Chemical and Biological Engineering and Division of Life Science,The Hong Kong University of Science and Technology,Clear Water Bay,Kowloon,Hong Kong(China)

出　　处：《CCS Chemistry》2020年第1期513-523,共11页中国化学会会刊（英文）

基　　金：We are grateful to acknowledge the National Basic Research Program(2013CB834502,2013CB834503);the National Natural Science Foundation of China(91527301,21434005,21525418,51773179,11302190,and 11432012);the Open Project of State Key Laboratory of Supramolecular Structure and Materials(sklssm201611)for financial support.

摘　　要：Mechanically interlocked molecules(MIMs)are prototypical molecular machines with parts that enable controlled,large-amplitude movement with one component positioned relative to another.Incorporating MIMs into polymeric matrices is promising for the designing of functional materials with unprecedented properties.However,the central issue is the challenges involved with establishing the mechanistic linkage between the single-molecule and the bulk material.Herein,we explore the mechanochemical properties and energetic details of a linear poly[2]catenane with strong intercomponent hydrogen bonding(IHB)revealed by single-molecule force spectroscopy.Our results showed that the individual linear poly[2]catenane chain exhibited typical sawtooth pattern,corresponding to the reversible unlocking and relocking transitions under external force or upon stimulations to dissociate or re-form the strong IHB.Furthermore,when a poly[2]catenane-based polymer gel was prepared using a thiol-ene click reaction between thiol-ended poly[2]catenane and a low-molecule-weight cross-linker,the resultant gel showed excellent mechanical adaptability and dynamic properties,which correlated well with the molecular-level observations.The unique poly[2]catenane structure also contributed to the gel formation with an extraordinary IHB-mediated swelling behavior and shape memory property.Thus our present results demonstrate the functioning of bulk material in a linear tandem manner from the behavior of a single molecule,a finding which should be applicable to other systems with versatile properties and promising applications.

关 键 词：polycatenane supramolecular polymer MECHANOCHEMISTRY single-molecule force spectroscopy 

分 类 号：O63[理学—高分子化学]