Liquid Crystalline Poly(3-hexylthiophene) Solutions Revisited: Role of Time-Dependent Self-Assembly
Liquid Crystalline Poly(3-hexylthiophene) Solutions Revisited: Role of Time-Dependent Self-Assembly
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DOI：
10.1021/acs.chemmater.5b00635
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发表时间：
2015-04-14
影响因子：
8.6
通讯作者：
Reichmanis, Elsa
中科院分区：
文献类型：
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作者：
Kleinhenz, Nabil;Rosu, Cornelia;Reichmanis, Elsa
聚（3-己基噻吩）（P3 HT）在三氯苯溶液中自组装，并表现出液晶有序时，限制在矩形毛细管。聚合物组装体的相对比例随时间增加，如通过紫外-可见光谱分析测定的。偏光显微镜（POM）揭示了双折射和monodomainlike长程有序的发展。显微拉曼光谱被用来计算取向有序参数，< P-2 >和< P-4 >，液晶P3 HT的解决方案。序参数< P-2 >随时间增加到0.35，表明各向异性增加。从解偏振动态光散射测量计算的解偏振比（p（v））点的高度有序的P3 HT纳米结构的形成时间依赖性，而低温透射电子显微镜用于棒状组件的直接可视化。POM表明，所观察到的各向异性可以保存在P3 HT膜从老化的解决方案。这些结果表明，P3 HT自组装导致共轭聚合物聚集体的液晶溶液，这可能会导致一个可行的方法优化有机电子器件应用的过程。这种有序和取向的共轭聚合物组装体对于高性能器件应用具有许多期望的属性，其中需要控制纳米至宏观尺度分子有序化的能力。
Poly(3-hexylthiophene) (P3HT) in trichlorobenzene solution self-assembles and exhibits liquid crystal ordering when confined to rectangular capillaries. The relative proportion of polymer assemblies increases with time, as determined by UV-vis spectroscopic analysis. Polarized optical microscopy (POM) reveals development of birefringence and monodomainlike long-range ordering. Micro-Raman spectroscopy was used to calculate the orientational order parameters, < P-2 > and < P-4 >, of the liquid-crystalline P3HT solutions. The order parameter < P-2 > increased with time up to 0.35, indicating increased anisotropy. The calculated depolarization ratio (p(v)) from depolarized dynamic light scattering measurements points to the time-dependent formation of highly ordered P3HT nanostructures, whereas cryogenic transmission electron microscopy was employed for the direct visualization of the rodlike assemblies. POM shows that the observed anisotropy can be preserved in P3HT films drawn from aged solutions. These results suggest that P3HT self-assembly leads to a liquid-crystalline solution of conjugated polymer aggregates, which may lead to a viable approach for optimization of processes for organic electronic device applications. Such ordered and oriented conjugated polymer assemblies have many desirable attributes for high-performance device applications, where the ability to control nano- through macroscale molecular ordering is required.