Controlling the Multiple Chiroptical Inversion in Biphasic Liquid‐Crystalline Polymers. (7th October 2021)

• Record Type: Journal Article
• Authors: Cheng, Xiaoxiao; Miao, Tengfei; Ma, Yafei; Zhu, Xiaoyan; Zhang, Wei; Zhu, Xiulin
• Is Part Of: Angewandte Chemie. Volume 133:Number 46(2021)
• Page Start: 24635
• Page End: 24641
• Publication Date: 2021-10-07
• Subjects: azobenzene -- chirality -- liquid-crystalline polymers -- polymerization-induced self-assembly -- supramolecular chemistry; Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.202109084
• Languages: English
• ISSNs: 0044-8249

Abstract

Abstract: While controlling the chirality and modulating the helicity is a challenging task, it attracts great research interest for gaining a better understanding of the origin of chirality in nature. Herein, structurally similar azobenzene (Azo) vinyl monomers were designed in which the alkyl chains comprised the chiral stereocenter with different achiral tail lengths. Combining the synchronous polymerization, supramolecular stacking and self‐assembly, the multiple chiroptical inversion of the Azo‐polymer supramolecular assemblies can be modulated by the tail length and DP of Azo blocks during in situ polymerization. The DP‐, UV light‐, temperature‐, aging time‐dependent chiroptical properties and liquid‐crystalline (LC) characterization indicated that the amorphous‐to‐LC phase transition and biphasic LC interconversion allow the transcription of intra‐chain π–π stacking, inter‐chain H ‐ and J ‐aggregation, thereby controlling the dynamic multiple reversal of supramolecular chirality. Abstract : The multiple chiroptical inversion in Azo biphasic liquid‐crystalline (LC) polymers is for the first time realized in situ through the tail length modification and degree of polymerization (DP) variation. The amorphous‐to‐LC phase transition and biphasic LC interconversion allow the transcription of three stacking modes, thereby controlling the dynamic reversal of supramolecular chirality.