Cheng Xiaoxiao, Miao Tengfei, Zhang Gong, Guo Jiaying, Zhou Zhenyang, Zhang Wei
State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials, Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, China.
School of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu 241000, China.
J Am Chem Soc. 2023 Aug 2;145(30):16474-16487. doi: 10.1021/jacs.3c02999. Epub 2023 Jun 29.
Controlling the secondary phase in chiral liquid-crystalline (LC) polymers is of great importance since it transfers and amplifies molecular information to the macroscopic properties. However, the chiral superstructures of the LC phase are determined exclusively by the inherent configuration of the parent chiral source. Here, we report the switchable supramolecular chirality of heteronuclear structures by the untraditional command between common chiral "sergeant" units and various achiral "soldier" units. Different chiral induction pathways between sergeants and soldiers were observed for copolymer assemblies with mesogenic and non-mesogenic soldier units, demonstrating the formation of a helical phase independent of the absolute configuration of the stereocenter. In the presence of non-mesogenic soldier units, the classical SaS (Sergeants and Soldiers) effect in the amorphous phase was observed; whereas in a full LC system, bidirectional command of sergeants was activated in response to the phase transition. Meanwhile, a full spectrum of morphological phase diagrams including spherical micelles, worms, nanowires, spindles, tadpoles, anisotropic ellipsoidal vesicles, and isotropic spherical vesicles were successfully achieved. Such spindles, tadpoles, and anisotropic ellipsoidal vesicles have rarely been obtained previously from chiral polymer systems.
控制手性液晶（LC）聚合物中的次级相非常重要，因为它能将分子信息传递并放大到宏观性质上。然而，LC相的手性超结构完全由母体手性源的固有构型决定。在此，我们报道了通过常见手性“中士”单元与各种非手性“士兵”单元之间的非传统指令实现的异核结构的可切换超分子手性。对于具有介晶和非介晶士兵单元的共聚物组装体，观察到了中士与士兵之间不同的手性诱导途径，这表明形成了与立体中心绝对构型无关的螺旋相。在存在非介晶士兵单元的情况下，在非晶相中观察到了经典的“中士与士兵”（SaS）效应；而在全LC系统中，中士的双向指令会响应相变而被激活。同时，成功获得了包括球形胶束、蠕虫、纳米线、纺锤体、蝌蚪、各向异性椭球囊泡和各向同性球形囊泡在内的全谱形态相图。此前，从手性聚合物系统中很少能得到这样的纺锤体、蝌蚪和各向异性椭球囊泡。
