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综述了近几年嵌段液晶共聚物在合成方面取得的新进展,主要包括活性聚合、液晶(或非液晶、低聚物与非液晶(或液晶)聚全物的单体反应、液晶低聚物与非液晶低降物直接反应和先制备非液晶嵌段共聚物再于侧链引入液晶基元四个方面。同时还简要地介绍了嵌段液晶共聚物的结构、性能以及今后的发展趋势。 相似文献
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聚合物网络分散液晶复合膜的制备与性能研究 总被引:1,自引:0,他引:1
报道了一种新型树脂基的聚合物网络分散晶复合膜材料。研究了基体材料的组成,液晶种类,液晶含量,聚合温度,紫外光强度及聚合时间等聚合物网络分散液晶复合膜性能的影响。扫描电子显微镜观测,发现这种材料是由两个连相互穿构成了属于聚合物球型。 相似文献
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本文综述了液晶二聚体、多爪型液晶及香蕉形液晶等几类非常规液晶材料的研究进展。结合笔者近几年的研究积累,着重介绍:(1)液晶二聚体的分子结构与液晶态结构及液晶二聚体所特有的奇偶效应与近晶多形性;(2)多爪型液晶的分子结构与液晶态结构的特点及由于兼有棒状分子与盘状分子的结构特点而具备的特殊的相变性质;(3)香蕉形液晶的分子结构与液晶态结构及香蕉形液晶所特有的手性与极化序。在介绍各类液晶材料的特点及研究热点的同时,围绕分子结构与液晶态结构的关系这一主题,深入讨论了各种液晶材料形成特殊分子排列及表现出特殊物理性质的机理。 相似文献
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以含有液晶基元的单体,2,5-双(4-甲氧基苯甲酰氧基)苯乙烯与丙烯醇,通过自由基共聚合反应,首次合成了一系列含液晶性单体和非液晶性单体两种结构的共聚物.采用DSC、偏光显微镜和X-衍射方法研究了共聚物的液晶行为,发现单体和所有的共聚物均有明显的热致液晶性及较宽的液晶态温度范围;随共聚物中液晶性单体含量增加,共聚物玻璃化转变温度Tg和热分解温度Td有所上升,但Tg的变化较小. 相似文献
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对金属有机液晶的分子形状、合成和性能进行了评述,为提高金属有机铁电液晶分子的偶极矩和电光响应速度进行了新的探索和分子设计。 相似文献
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发光液晶高分子结合了液晶高分子的有序性、稳定性、力学性能和发光分子的发光特性,有着广阔的应用前景。为了获得高效的发光液晶高分子,不同结构的发光液晶高分子被成功地设计与合成,包括主链型、侧链型、“甲壳”型发光液晶高分子、发光液晶高分子网络等。同时,分子结构、液晶相结构与光物理性质的关系也得到了相应的深入研究。本文总结了发光液晶高分子的最新研究进展,详细介绍了不同类型发光液晶高分子的分子结构设计合成、结构与性能、相关应用,并对其发展前景进行了展望。 相似文献
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甲壳型液晶高分子研究进展与展望 总被引:3,自引:0,他引:3
简要介绍了甲壳型液晶高分子的模型理论, 概述了当前国内外对甲壳型液晶高分子设计、 液晶相态、 性质及基于甲壳型液晶高分子的嵌段共聚物体系的设计和自组装性质等研究进展, 展望了今后的研究方向. 相似文献
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新型侧链液晶M5MPP/MMEANB高聚物的合成与表征 总被引:1,自引:0,他引:1
以4,4'-二羟基联苯、4-硝基苯胺、二溴己烷、甲基丙烯酸、氯代乙醇为原料合成了单体甲基丙烯酸[5(4'-甲氧基联苯4氧基)戊基]酯(M5MPP)、4-硝基偶氮苯基甲基-2-甲基丙烯酸酯基乙胺(MMEANB),并完成了单体的聚合和共聚,得到了含有非线性光学活性基团(NLO)的侧链液晶高分子,对其结构进行了表征.结果表明,均聚物PM5MPP及共聚物(M5MPP/MMEANB)属双向液晶高分子;PMMEANB属于非晶性高分子.证实了分子间吸电子与给电子基团相互作用有利于提高液晶高分子热稳定性,共聚物(M5MPP/MMEANB)具有较宽的液晶相温度范围. 相似文献
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Jason R. Greuel Timothy E. Andrews Justin J. Wichman Joshua D. Tessner 《Liquid crystals》2013,40(12):1515-1520
A series of supramolecular polymers and networks with variable liquid crystalline characteristics have been created. These species are formed through the benzoic acid/pyridine hydrogen bonding of a flexible bis-acid and a mixture of a rigid bis-pyridyl and non-mesogenic tris- and bis-pyridyl molecules. The tris networked systems displayed liquid crystalline characteristics up to and including 31.0% netpoint inclusion. Above this concentration, only crystalline and melting behaviours were observed. The bis-containing polymer system displayed liquid crystalline characteristics up to and including 22.5% inclusion. The phenomenon observed in the tris system would seem to be linked to a statistical correlation of hydrogen bond acceptors and donors. The elimination of liquid crystallinity at lower concentrations of the bis-pyridyl dopant could be attributed to the lower melting nature of that species. Smectic phases were found in both series of complexes in loadings up to 10% of the non-liquid crystalline component. There was also no observed phase segregation of the species after multiple heat/cool cycles and extended periods of time in the isotropic state. This would indicate that the thermodynamically more stable mesogenic phase cannot out-compete the non-liquid crystalline network. 相似文献
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The morphology and optical properties of polymer stabilized liquid crystals formed in a more highly ordered low molecular weight liquid crystal solvent were studied. Tetrafunctional, mesogenic monomers (with and without flexible spacers) were polymerized in isotropic, nematic and smectic phases of the LC solvent (4′-octyl-4-cyanobiphenyl) and studied with scanning electron microscopy and cross-polarized light microscopy. The network morphology of the nematic and isotropic phase polymerizations showed strong similarities with the corresponding polymerizations in other solvents. Polymerization in the smectic phase, however, resulted in marked increases in network order and directionality. Most dramatically, even the polymer without flexible spacer formed a fibrous network of rodlike units, in contrast to the random, beaded texture formed by the same polymer in nematic or isotropic conditions. Correspondingly, a large increase in birefringence demonstrated significant polymer orientation and more effective orientational interaction with the liquid crystalline solvent. 相似文献
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Helou Xie Tianhui Hu Xuefei Zhang Hailaing Zhang Erqiang Chen Qifeng Zhou 《Journal of polymer science. Part A, Polymer chemistry》2008,46(22):7310-7320
A novel combined main‐chain/side‐chain liquid crystalline polymer based on mesogen‐jacketed liquid crystal polymers (MJLCPs) containing two biphenyls per mesogenic core of MJLCPs main chain, poly(2,5‐bis{[6‐(4‐butoxy‐4′‐oxy‐biphenyl)hexyl]oxycarbonyl}styrene) (P1–P8) was successfully synthesized via atom transfer radical polymerization (ATRP). The chemical structure of the monomer was confirmed by elemental analysis, 1H NMR, and 13C NMR. The molecular characterizations of the polymer with different molecular weights (P1–P8) were performed with 1H NMR, gel permeation chromatography (GPC), and thermogravimetric analysis (TGA). Their phase transitions and liquid‐crystalline behaviors of the polymers were investigated by differential scanning calorimetry (DSC) and polarized optical microscope (POM). We found that the polymers P1–P8 exhibited similar behavior with three different liquid crystalline phases upon heating to or cooling in addition to isotropic state, which should be related to the complex liquid crystal property of the side‐chain and the main‐chain. Moreover, the transition temperatures of liquid crystalline phases of P1–P8 are found to be dependent on the molecular weight. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 7310–7320, 2008 相似文献
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甲壳型液晶高分子的发展很大程度上依赖于聚合物自组装的发展,而各种可设计、可预测、可调控的自组装策略的涌现,将甲壳型液晶高分子研究推向前所未有的高度,同时也极大地丰富了高分子化学与物理的内容,提升了研究水准.研究表明,侧链"甲壳效应"在调控甲壳型液晶高分子有序结构等方面有着重要作用.本综述从甲壳型液晶高分子设计合成、液晶相态调控、嵌段共聚物自组装和功能化应用等方面,总结和评述了近年来该领域国内的最新研究进展.最后,本综述总结了甲壳型液晶高分子在发展中所面临的主要问题,并对其发展趋势进行了展望. 相似文献