以富勒烯为核的树形盘状液晶大分子的设计合成和光电特性研究

Liquid crystalline dendrimers (LCDs) with precisely controlled molecular architectures and a large amount of liquid crystal moieties, are a class of functional polymers with various promising applications. In contrast with intensively studied calamitic mesogens based LCDs, thus far surprisingly limited progress has been made on discotic LCDs so far, as well as certain problems remain unsolved for LCDs such as inadequate functions and applications. This proposal aims to develop a kind of discotic LCDs decorated with a fullerene core by making full use of their structural advantages that can be precisely regulated at the molecular level. These LCDs may assemble into hierarchical columnar liquid crystal superstructures through microsegregated columnar stacking of fullerene core and peripheral triphenylene discotic units. Thus by combining the hole carrier transport of the triphenylene columns and the electron transfer of fullerene core, a class of double-cable discotic liquid crystal organic optoelectronic materials will be constructed. In this project, the structure-function relationship between composition parameters, liquid crystal properties, and performance of ambipolar charge transport of these LCDs will be clarified. Finally, this research will provide new ideas for the controlled preparation of multifunctional dendrimers, and open a new avenue to the optoelectronic applications of liquid crystalline polymer materials.

树形液晶大分子具有精确可控的分子结构和大量的液晶基元，因此是一类具有广泛应用前景的功能高分子。目前对树形棒状液晶大分子的组装过程已有较为清晰的认识，但对基于盘状液晶的树形大分子的研究却尚未深入，同时其功能单一且应用不足。申请人利用树形大分子结构可在分子水平精确调控的优势，设计出一类以富勒烯为核的树形盘状液晶大分子。利用富勒烯核与外围苯并菲盘通过微分相组装分别独立堆积成柱，进而有序组织形成多层次柱状液晶超结构；融合苯并菲柱的空穴传输和富勒烯的电子迁移性能，构筑一类具有良好加工性能的双缆型树形盘状液晶大分子多功能材料。阐明这种液晶大分子组成参数、液晶结构、和双极性载流子传输性能的构效关系。本项目将为制备结构可控的多功能树形大分子提供新思路，也为液晶聚合物材料光电应用开辟新途径。

将液晶性能和树形大分子的拓扑结构相结合形成的树形液晶大分子，近年来受到广泛关注并成为液晶研究的一个前沿热点领域。本项目将功能液晶基元引入树形大分子体系，设计并制备出结构可控的树形液晶大分子，深入研究了组成参数对液晶结构及光电性能的作用机制与影响规律，并将所制备的液晶大分子材料应用于载流子传输及固态发光等领域。本项目取得的代表性性成果包括：（1）制备出以富勒烯为核的树形盘状液晶大分子，融合苯并菲柱的空穴传输和富勒烯的电子迁移性能，成功构筑出双缆型液晶大分子材料；（2）发展了加工方法依赖的组装动力学过程控制策略，达到了对液晶大分子复杂组装过程的有效调控，实现了对超分子组装结构的精确裁剪；（3）提出了液晶分子构象平衡方法，构筑了发光、导电和刺激响应等多功能集成的液晶材料，克服了现有液晶材料功能单一、操纵性差的关键问题。通过本项目的研究，迄今已在Macromolecules（2篇）、ACS Applied Materials & Interfaces（2篇）、Journal of Materials Chemistry C（1篇）、Materials Chemistry Frontiers（1篇）等期刊上正式发表SCI论文9篇；申请中国发明专利1项；培养硕士研究生6人（毕业3人）。以上研究成果被Macromolecules、ACS Nano等国际著名SCI期刊正面引用和积极评价。