具有热活化延迟荧光（TADF）效应的蓝光聚芳醚的设计合成与性能研究

As for the typical conjugated polymers, it seems to be very difficult to realize blue thermally activated delayed fluorescence (TADF) because of their lower triplet energies than 2.7 eV. To solve such a problem, herein we plan to develop blue poly(arylether)s showing excellent TADF. In this case, the blue TADF small molecules are linked together by oxygen to form a basic poly(arylether) structure, where the conjugation of the polymeric backbone is interrupted to avoid the electronic communication between two neighboring TADF units. Consequently, the resultant polymer is expected to keep the blue TADF emission of the small molecule. At the same time, the blue, green and red hyperfluorescence with low-cost, high-efficiency and good device stability will also be exploited by using the blue poly(arylether)s as the hosts and the fluorescent emitters as the guests. We believe that this project will shed light on the design and application of efficient blue TADF polymers.

针对传统共轭高分子因三线态能级过低（< 2.7 eV）而难以实现蓝光TADF的问题，本项目旨在采用聚芳醚作为高分子骨架，发展具有热活化延迟荧光（TADF）效应的蓝光聚芳醚材料。核心在于设计合成高性能的蓝光TADF小分子作为聚合单体，通过均聚或共聚的连接方式形成聚芳醚结构，期望利用O原子来打断共轭，避免相邻蓝光TADF单元之间的电子耦合，从而使得高分子能够保持小分子的蓝光TADF特性。同时，采用蓝光TADF聚芳醚作为主体和荧光染料作为客体，开发低成本、高效率和良好器件稳定性的蓝绿红三基色超荧光体系，为蓝光高分子TADF材料的设计与应用开辟出新途径。

热活化延迟荧光（TADF）和纯有机室温磷光（RTP）能够同时利用单线态和三线态激子，获得100%理论内量子效率，在OLED显示中表现出潜在的应用前景。因此，本项目围绕聚芳醚高分子骨架进行拓展，开展了蓝光热活化延迟荧光聚芳醚、D-O-A型纯有机室温磷光聚芳醚和小分子、热活化延迟荧光高分子的全新设计三方面的研究工作，取得以下创新成果：①采用蓝光TADF单元嵌入到聚芳醚骨架的分子设计思路，调控共聚单元，设计合成了系列蓝光TADF聚芳醚，外量子效率高达13.2%，色坐标为(0.18,0.32)。在此基础上，进一步调控蓝光TADF单元，实现了器件寿命的提升和深蓝光发射。②采用D-O-A结构，设计合成了系列D-O-A型纯有机室温磷光材料，在聚芳醚和小分子体系分别获得了高达9.7%和15.8%的器件外量子效率。同时，基于D-O-A型RTP小分子敏化磷光铱配合物或多重共振TADF的途径，组装了高效蓝光、绿光、黄光和红光敏化型器件，最大外量子效率分别为26.4%、21.7%、21.8%和22.8%，色坐标分别为(0.12,0.45)、(0.30,0.63)、(0.48,0.50)和(0.64,0.35)。③在聚芳醚之外，采用TADF+Polymer、TADF+Linker和D-A型共轭高分子三种分子设计原则，发展了系列高性能TADF高分子。尤其是D-A型共轭TADF高分子，实现了有效的掺杂和非掺杂器件，最大外量子效率分别为24.0%和15.3%。该项目的顺利实施，为发展下一代新兴有机电致发光材料开辟出新途径。