基于四硫富瓦烯液晶化合物的合成、表征及其介晶性研究

发布时间：2018-03-20 13:46

本文选题：基于　切入点：四硫　出处：《长春工业大学》2017年硕士论文　论文类型：学位论文

【摘要】：近年来,四硫富瓦烯及其衍生物凭借其独特的电化学性能与光物理性能,吸引了人们的广泛关注,在有机光电材料的各个领域中发挥着重要的作用,被认为是一类很有应用潜力的构筑单元。其中,具有介晶性的四硫富瓦烯衍生物在有机导体材料领域具有重要的研究价值,这是由于其在液晶区间内的宏观排列更加有序,从而使结构缺陷减少。迄今为止,人们已经成功合成出数量庞大的四硫富瓦烯衍生物,然而其中具备介晶性的化合物却非常少见,并且具有介晶性的四硫富瓦烯衍生物的合成难度大,分离复杂,限制了其在材料领域的发展。本文设计并成功合成了一系列以四硫富瓦烯为构筑单元的目标化合物4a~e与目标化合物7a~e,并证明其具有液晶性。目标化合物均以四硫富瓦烯作为结构单元,同时也作为分子结构中的刚性部分,我们在其周围引入了不同长度的4'-烷氧基-4-氰基联苯作为柔性链来调整分子中柔性部分与刚性部分的比例,逐渐增加液晶分子的流动性。所有目标化合物的结构均以核磁氢谱、碳谱、红外吸收光谱与质谱来进行表征。本文通过热重分析(TGA)来对目标化合物的热稳定性进行研究,测试结果表明目标化合物4a~e与目标化合物7a~e均有很好的热稳定性。通过差示扫描量热法(DSC)与偏光显微镜(POM)的观察相结合来对目标化合物4a~e与目标化合物7a~e的液晶性进行表征,测试结果表明所合成的目标化合物都具有液晶性,并且有较宽的液晶区间,在冷却过程中并没有出现结晶现象,而是相变为玻璃态液晶,随着目标化合物末端柔性链长度的变化,液晶相态也随之发生变化,呈现出了不同的液晶织构,这说明柔性链的长度与化合物的结构影响了液晶分子的排列情况。通过循环伏安法(CV)来对目标产物的氧化还原行为进行研究,我们发现目标化合物4与目标化合物7都具有两个准可逆的单电子氧化峰,可以作为很好的电子给体。以上一系列研究表明,目标化合物4与目标化合物7都具有液晶性,并且液晶行为受柔性链长度的影响,在有机光电材料领域有很大的应用潜力。
[Abstract]:In recent years, tetrathiafulvalene and its derivatives have attracted wide attention due to their unique electrochemical and photophysical properties, and play an important role in various fields of organic optoelectronic materials. Tetrathiafurane derivatives with mesomorphic properties have important research value in the field of organic conductor materials because of their more ordered macroscopic arrangement in liquid crystal region. So far, we have successfully synthesized a large number of tetrathiofovalene derivatives, but there are very few compounds with mesomorphic properties. Moreover, the synthesis of tetrathioflavene derivatives with mesomorphic properties is difficult and complex. In this paper, a series of target compounds with tetrathiafurane as the building unit were designed and successfully synthesized. It was proved that the target compounds were liquid crystalline. Fulvalene as a structural unit, At the same time, as the rigid part of the molecular structure, we have introduced different lengths of 4-alkoxy-4-cyanobiphenyl around it as a flexible chain to adjust the ratio of the flexible part to the rigid part of the molecule. The structure of all the target compounds was characterized by NMR, C, IR and MS. The thermal stability of the target compounds was studied by thermogravimetric analysis (TGA). The results show that the thermal stability of the target compound 4aAne and the target compound 7ane is very good. The liquid crystal properties of the target compound 4aAne and the target compound 7aAne are characterized by the observation of differential scanning calorimetry (DSCC) and polarizing microscope (POM). The test results show that the synthesized target compounds are liquid crystalline and have a wide liquid crystal range. There is no crystallization in the cooling process, but the phase is changed into glassy liquid crystal. With the change of the length of the flexible chain at the end of the target compound, the liquid crystal phase also changes, showing different liquid crystal texture. This indicates that the length of the flexible chain and the structure of the compound affect the arrangement of liquid crystal molecules. The redox behavior of the target product is studied by cyclic voltammetry (CV). We found that both target compound 4 and target compound 7 have two quasi-reversible single electron oxidation peaks, which can be used as a good electron donor. The liquid crystal behavior is affected by the length of flexible chain and has great application potential in the field of organic optoelectronic materials.
【学位授予单位】：长春工业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：O622.7;O753.2

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