Diselenide as a Dual Functional Mechanophore Capable of Stress Self-Reporting and Self-Strengthening in Polyurethane Elastomers  

作　　者：Xiaopei Li Fan Yang Yiran Li Cheng Liu Peng Zhao Yi Cao Huaping Xu Yulan Chen 

机构地区：[1]Department of Chemistry,Tianjin Key Laboratory of Molecular Optoelectronic Science,Tianjin University,Tianjin 300072 [2]Department of Physics,Collaborative Innovation Center of Advanced Microstructures,National Laboratory of Solid State Microstructure,Nanjing University,Nanjing,Jiangsu 210093 [3]Department of Chemistry,Key Laboratory of Organic Optoelectronics and Molecular Engineering,Tsinghua University,Beijing 100084 [4]College of Chemistry,State Key Laboratory of Supramolecular Structure and Materials,Jilin University,Changchun,Jilin 130012

出　　处：《CCS Chemistry》2023年第4期925-933,共9页中国化学会会刊（英文）

基　　金：support of this research by the National Natural Science Foundation of China(grant nos.21734006 and 21975178);the National Key Research and Development Program of China(grant nos.2017YFA0207800 and 2017YFA0204503)is gratefully acknowledged.

摘　　要：Unlike biological materials that can sense mechanical force and actively remodel locally,synthetic polymers typically break down under stress.Molecular-level responses to damage with both stress-reporting and self-strengthening functions are significant yet difficult to realize for synthetic polymers.To overcome this challenge,chemo-mechanical coupling into polymers that can simultaneously ameliorate mechanical,optical,or other functional properties of a polymer combined with mechanical treatment will offer a new principle for materials design.Here,we report a kind of elastomer in which destructive forces are channelled into productive and bond-forming reactions by using diselenide(Se–Se)as a mechanophore.Polyurethane has been functionalized with labile Se–Se bonds,whosemechanical activation generates seleno radicals that trigger radical transfer and cross-linking reactions in situ.These reactions are activated efficiently in a mechanical way by compression in bulk materials.The resulting covalent networks possess turn-on mechano-fluorescence and increased moduli,which provide the functions of stress reporting,mechano-healing,and mechano-remodeling for the deformed film.This study not only illuminates themechano-responsive nature of Se–Se bonds in the bulk state but also paves the way for the development of new stress-responsive materials.

关 键 词：DISELENIDE mechano-responsive polymers SELF-STRENGTHENING polymermechanochemistry stress sensing 

分 类 号：TQ317[化学工程—高聚物工业]