手性聚酰亚胺的合成、结构与性能

Synthesis,Structure and Properties of Chiral Polyimides

手性聚酰亚胺逐渐成为手性高分子研究的一个重要方面,在分子识别、对映体选择性分离、不对称催化等领域有潜在的应用,日益受到研究者的重视。本文综述了近二十年手性聚酰亚胺的研究进展,将手性聚酰亚胺按照手性结构的引入方式分为侧链手性、主链中心手性和主链轴手性三种类型,并分别加以总结和阐述,介绍了具有代表性的光活性聚酰亚胺的结构、合成和性能,特别关注了手性聚酰亚胺的高次结构的形成以及与其手性光活性相关的性能与应用。最后,本文阐述了手性聚酰亚胺研究面对的挑战与未来发展前景,探索手性聚酰亚胺的合成、性质和应用,建立合理的模型和分析手段,深入探讨手性聚酰亚胺的高次结构仍然是值得深入研究的重点方向。

As an important research field of chiral polymers,chiral polyimides have attracted much attention from polymer community for their potential applications in molecular recognition, enantioselective separation, and asymmetric catalysis. This paper reviews the advance on chiral polyimides in past 20 years. Optically active polyimides are divided into three types according to the position and type of the chiral groups,which are the chirality on side chain,the central chirality on main chain,and the axial chirality on main chain. Each type of chiral polyimides is summarized in details with representative structure,synthesis,properties,the formation of secondary structure,and applications related to the chiro-optical activity of the polymers. Chiral polyimides prepared by post-derivation on the side chains of the achiral backbones supplied chiral alignment surfaces to induce the alignment of liquid crystals in forms with enantiomeric excess or with specific directions. Chiral polyimides with chiral groups in main chains are prepared from chiral dianhydrides or chiral diamines that are usually derived from amino acids,trans-1,2-cyclohexanediamine,spirocyclic compounds,and binaphthyl derivatives. Studies have shown that both central chiral monomers and axial chiral monomers induced the formation of secondary structure by the chiral polyimides. Optical rotation and circular dichroism（ CD） are still the few tools for the investigations to the chiral secondary structure of chiral polyimides. At the end of the review,we present the challenges and the future directions of the developments on chiral polyimides. Despite quick developments in recent years,preparations,structures,and applications of chiral polyimides,as well as scrutiny on the chiral secondary structure with rationale models and methodologies,are worthy of paying much attention.