共轭聚合物在多组分共混体系中的聚集结构研究进展

Research Progress on Aggregation Structure of Conjugated Polymers in Multicomponent Blends

基于本体异质结的聚合物太阳电池性能与相分离结构特别是聚合物的聚集结构密切相关.本文综述了一些典型共轭聚合物聚集结构方面的研究进展,详细介绍了基于齐聚噻吩、二噻吩、苯并二噻吩及噻吩衍生物的D-A共聚物、二维共轭聚合物以及嵌段共聚物等体系的聚集结构特点,系统总结了一系列共轭聚合物在不同共混物、处理溶剂、退火温度、共混比例、分子量、侧链原子或基团等条件下相应的聚集结构变化规律.在众多共轭聚合物中,研究最多的是D-A共聚物,故作重点介绍,而二维共轭聚合物、嵌段共聚物作简要介绍.

Conjugated polymers have attracted much attention due to their unique electronic properties and solution processing methods.The rigid and planar conformational backbone manifests extendedπ-system and the flexible alkyl chain assures the sufficient solubility,which contribute to their tuneable physical and chemical properties and increase the tolerance of film forming and mechanical flexibility.In general,the orthogonal design of functional fragments for conjugated polymers make it accessible forπ-stacking of conjugated segments and lamellar stacking of interchain interactions.Short-range aggregates or long-range microcrystals would be selectively and/or successively formed by controlling their chemical structures and processing conditions.Such stacking structure in the phase-separated domain is crucial to the high efficient performance of bulk heterojunction solar cells.The aggregation structure of some typical conjugated polymers has recently been reviewed with a view to providing reference for the development of optoelectrics in this study.Here,D-A copolymers based on oligothiophene,dithiophene,benzothiophene and thiophene derivatives,two-dimensional conjugated polymers and block copolymers are introduced in detail.The aggregation structure of a series of conjugated polymers is systematically summarized by using the different processing techniques,such as selective counterpart components,treating solvents and annealing temperature.In addition,the intrinsic motivation of the controllable aggregation structure is discussed from the aspects of molecular weight and side chain groups.