聚咔唑聚芴盘状高分子液晶的合成与光电性能

Discotic liquid crystals are important organic semiconductors, and have shown substantial application in organic light-emitting diodes (OLEDs), photovoltaic solar cells, and field-effect transistors (FETs). For introducing discotic liquid crystal mesogens as side-chain into the conjugate polymer by flexible spacer can improve the materials' solubilty and processbility, promote the molecular packing order, realize fast charge carrier mobility and anisotropic opto-electronic properties..In this project, we will focus our research work on following issues: (1)synthesis series of conjugated polyfluorene and polycarbazole with triphenylene discogens as the side group;(2)investigate the inter- and intra-molecular interactions between discogens and main chains, for obtaining higher ordered columnar mesophase and fast hole or electron mobility, and luminenscent properties;(3)transition metal catalysts (Ni, Pd, Cu) system for chain-growth cross coupling polymerization and oxidative coupling will be optimized for obtaining new conjugated polymeric semiconductors;(4)using thermal analysis methods (DSC and TGA), electronic microscopy and X-ray diffraction to anlayze the phase behaviors of the polymer materials, use photo spectroscopy and electrochemical methods to investigate their opto-electronic properties;(5)the time-of-flight (TOF) method will be used for measure the charge carrier mobility of the materials;(6)the application of the materials in organic electronic devices, such as OLEDs, FETs, and solar cells..We belive that our study on the synthesis and opto-electronic properties of conjugated polyfluorene and polycarbazole with discotic liquid crystalline properties will have important values in academic and in industry.

盘状液晶是一类新型有机半导体材料，它在有机发光二级管，太阳能电池，场效应晶体管中有广阔的应用前景。带有盘状液晶基元侧基的共轭高分子，将有良好的溶解性和溶液加工性，提高其分子聚集的有序程度，改善其电荷传输的各向异性和迁移率。本项目将设计合成系列新型带有苯并菲盘状液晶基元的聚芴和聚咔唑高分子材料。研究主链与侧链间相互作用，聚合物形成高度有序的柱状液晶相和优良的光电性质是本项目的研究目标。共轭聚合物合成将通过金属催化(Pd,Ni,Cu)人名反应实现。金属离子残留对半导体性质的不利影响将通过多次萃取消除。通过热分析、变温X射线衍射、电子显微镜研究聚合物的热稳定性和自组装有序结构和相态。探索盘状液晶基元作为侧基对共轭聚合物有序度和光电性能的影响。光谱法和电化学方法研究材料的光电性质，用飞行时间法测试聚合物的电荷迁移率。本项目将合成新型有机聚合物半导体材料，具有重要的学术价值和应用前景。

液晶半导体材料作为新型有机半导体近年来受到学术界和工业界的持续关注：其独特的自组装有序性和较高载流子迁移速率使其在有机场效应晶体管（OFET）,有机发光二极管（OLED）,有机太阳能电池，分子传感器的领域有广阔的应用前景。本项目充分利用苯并菲，苝二酰亚胺、咔唑、芴、吐昔烯、芘等共轭芳烃模块，通过金属Pd和Ni催化的Suzuki, Sonogashia, Still偶联反应, 以及FeCl3/MeNO2作为氧化剂的Scholl反应环化脱氢芳基化, Cu催化点击反应，合成了多个系列的共轭高分子和多聚体。通过核磁共振谱和高分辨质谱对其化学结构进行了表征。通过热台偏光显微镜(POM)，差示扫描量热仪 (DSC)，热失重分析仪 (TGA)对材料的热稳定性，相转变温度，偏光显微织构等进行了研究。扫描隧道显微镜(STM)和小角X-射线散射 (SAXS)技术对材料自组装单层结构(SAM)和聚集态有序结构进行了研究。材料的半导体性质通过瞬态光电流飞行时间法 (TOF)进行了测试。部分化合物还就行了场效应晶体管器件 (OFET)评估。本项目获得了化学结构丰富，电子和空穴迁移率在10-4 ~ 10-2 cm2/(Vs)的柱状相液晶材料，以及空穴迁移率和晶体管迁移率0.1 ~ 2 cm2/(Vs)的近晶相液晶半导体材料，在薄膜晶体管，有机太阳能电池有应用价值。材料分子结构-聚集态液晶有序相态-电荷迁移速率之间关系有较大科学价值，为进一步深入研究液晶半导体材料及应用打下了坚实的基础。