Synthesis and Structure-Property Relationship of Star Dyades and Triades as Novel, Filled Liquid Crystals

形状持久的三臂寡聚（苯乙烯）恒星介质形成柱状液晶介相，尽管其线性共轭臂之间的自由体积很大。作为供体的这些星形介原的低聚（苯乙烯）臂与富勒烯构件通过柔性间隔物相互连接，形成供体-受体二元体。这里的空隙被共价结合的富勒烯客体分子占据。这些分子的自组装导致了具有纳米分离的供体-受体结构的新型填充柱状中间相。结构控制是通过改变垫片长度、连接位置、共轭支架长度和周边柔性链来实现的。通过引入低聚（乙烯氧基）或支链来实现低于200°C的清除温度。以卟啉和酞菁核为基础的三联星，其上附着着含富勒烯的二苯乙烯类臂，是这一概念的延伸。用x射线散射技术、紫外可见光谱和荧光光谱研究了材料在溶液和液晶状态下的结构。结果允许使用程序包Materials Studio建立模型，并导致对结构-属性关系的深入了解。如果能实现各向同性排列，供体和受体发色团在柱状结构中的密集包装应该允许快速电荷传输到器件中的电极。因此，材料系统在其光伏特性方面具有特殊的兴趣。电荷分离和输运不仅可以通过定制的供体-受体介元来优化，还可以通过制备具有四个'键的富勒烯客体的三星型化合物、没有富勒烯的恒星和合适的功能化富勒烯之间的混合物来优化。低聚乙烯氧基链的引入提高了材料的介电常数，有望促进电荷分离。液晶状态将用于固体薄膜中柱的正确排列。随后将制作光伏液晶电池，并与Grelet教授（波尔多）合作研究其光伏性能。

Shape-persistent three-armed oligo(phenylenevinylene) star mesogens form columnar liquid crystalline mesophases despite the large free volume between their linear conjugated arms. The interconnection of the oligo(phenylenevinylene) arms of these star mesogens, which are donors, with fullerene building blocks via flexible spacers results in donor-acceptor dyads. Here the void is occupied by covalently bound fullerene guest molecules. The self-assembly of these molecules leads to novel filled columnar mesophases with nanosegregated donor-acceptor structures. The structural control is achieved by variation of the spacer length, the connection position, the length of the conjugated scaffold and the peripheral flexible chains. Clearing temperatures below 200 °C are realized by introduction of oligo(ethyleneoxy)- or branched chains. Star triades, based on Porphyrin and Phthalocyanine cores, to which fullerene containing stilbenoid arms are attached, are an extension of this concept. The materials structures are investigated by X-ray scattering techniques, UV-Vis- and fluorescence spectroscopy in solution and liquid crystal state. The results allow the set-up of models with the program package Materials Studio and lead to the in-depth knowledge of the structure-property relationships. The dense packing of donor and acceptor chromophores in a columnar structure should allow a fast charge transport to the electrodes in a device, if a homeotropic alignment can be achieved. The materials systems are therefore of special interest with respect to their photovoltaic properties. Charge separation and transport will be optimized not only by the tailor-made donor-acceptor mesogens but also by the preparation of mixtures between star triades with four ´bound fullerene guests, stars without fullerenes and suitable, functionalized fullerenes. The introduction of oligo(ethyleneoxy) chains are promising to promote charge separation owing to the increase of the materials dielectric constant. The liquid crystal state will be used for the correct alignment of the columns in thin solid films. The photovoltaic liquid crystal cells will be fabricated subsequently and their photovoltaic properties will be studied in collaboration with Prof. Grelet (Bordeaux).