Effect of Molecular Weight on Liquid Crystal Photoalignment by Photosensitive Polyester Containing Thrifluoromethyl Moieties

We investigate the liquid-crystal （LC） alignment direction on photoalignment films formed from photosensitive polyester containing thrifluoromethyl moieties （PPDA） with various molecular weights by crossed polarized optical microscopy. It is found that LC alignment behaviour changes with molecular weight of PPDA. The LC alignment on PPDA irradiated films with the highest molecular weight is homogeneous, while those with low and intermediate molecular weights are homeotropic. However, surface morphologies show weak dependence on molecular weight. The surfaces are smooth and there is no clear morphological anisotropy on these aligned films observed by an atomic force microscope. The surface energies of the irradiated films are also measured by using an indirect contact-angle method where both surface energy and its polar component, increase with increasing molecular weight. Different polar surface energies can be considered as a main reason for different alignment characteristics.     

线圈型全光纤偏振器的研究

本文采用等效电流法对线圈型全光纤偏振器进行了分析计算.对应于保偏光纤中两正交传输基模的消光比,提出了一种分析保偏光纤弯曲损耗的新方法,这种方法基于将保偏光纤两个不同偏振模式分别等效为两个普通圆光纤的基模,等效参数通过测量不同偏振模式的模场半径来确定.实验证明这种理论计算方法与实验结果一致.最终,我们研制出的线圈型光纤偏振器在1.31μm工作波长下,实测消光比达30dB以上,工作偏振模式插入损耗≤3dB.     

液晶研究（Ⅰ）──4＇－酰基－4－羟基－1，1＇－联苯酯类液晶的合成与性质

以４＇－羟基联苯为原料合成了８种新型４＇－酰基－４－羟基联苯酯类化合物．除化合物５＿ｈ外，均为新的近晶相液晶化合物．它们具有较宽的相变温度范围和较高的热稳定性．用偏光显微镜和差热分析仪研究了它们的相行为，讨论了分子结构对液晶相行为的影响．     

外电场下光聚合反应动力学的表征方法

外电场下光聚合反应动力学的表征方法李从武，潘昂上海材料研究所，上海２０００８２）关键词光聚合反应、液晶、外电场、动力学、表征近年来，液晶单体在外场（电场、磁场和剪切力）下在位光聚合反应的研究工作受到了很大的关注［’，ＺＩ．众所周知，热致型侧链高分子液...     

meso-四(对烷氧苯基)卟啉金属配合物的合成和性能研究(Ⅳ)

合成了系列卟啉乙酸合锰配合物9个,其中6个为未见文献报道的新化合物.用UV,1HNMR,IR,MS,元素分析等表征确证了配合物的结构,总结了锰与卟啉类配体配合的IR,UV,1H NMR判据.采用差示扫描量热法(DSC)和偏光显微镜(PM)研究了该系列配合物的液晶性能,发现8个配合物具有液晶性.考察了烷氧基链长、配位金属离子和分子空间结构对液晶性能的影响.     

引入离子基团改善聚苯乙烯和热致液晶聚合物的相容性Ⅰ.热性能和形态

ＤＳＣ和ＳＥＭ研究结果表明聚苯乙烯与一种热致液晶聚合物完全不相容。共混体系具有与组分无关的Ｔｇ，并且表现出明显的两相结构。将ＰＳ进行化学改性，随中和盐离子的变化有；酸式，Ｌｉ，Ｎａ，Ｚｎ和Ｍｎ盐五种形式。用ＤＳＣ和ＳＥＭ对ＬＣＰ与ＳＰＳ共混物的热性能和形态进行了分析和表征。     

一种新型侧链液晶聚合物的喇曼光谱研究

The Raman scattering on a novel liquid crystal side chain polymer, poly-2,5-bis (p-meth-oxybenzoyloxy) styrene, has been performed. We observed that the characteristic Raman sp-ctra of the vinyl group in the monomer changed much deeply in the polymer, especially for the Raman line correponding to the C=C of the vinyl group which disappeared completly in the polymer. Contrast with that, the Raman spetra of the rest group did not present any substantial difference between the monomer and the polymer. These experimental facts show-ed that the vinyl group of the monomer was tranfered to the polymeric backbone while the chemical structure of the mesogenic unit in the monomer remained after the polymerization,and also conformed that it was successful in the synthesis of a liquid crystal side chain plymer without a flexible spacer between the mesomorphic unit and the molecular main chain.     

溴原子取代对二茂铁液晶化合物介晶性的影响

二茂铁液晶因其独特的稳定性和易于衍生化受到研究人员的青睐[1- 8] 。我们曾经报道过一类单取代二茂铁液晶的合成与介晶性[9] 。这里我们报道另外一类二茂铁单取代液晶 ,并对分子的长度、溴原子取代对介晶性的影响进行探讨。合成路线如下 :1　实验部分ＢｒｕｃｋｅｒＡＣＥ -2 0 0ｓｐｅｃｔｒｏｍｅｔｅｒ,ＣＤＣｌ3作溶剂。ＮｉｃｏｌｅｔＭａｇｎａ-ＩＲ 5 0 0Ｓｐｅｃｔｒｏｍｅｔｅｒ,ＳｅｒｉｅｓⅡ ,ＫＢｒ压片。ＷＲＳ -ＩＡ ,ＣａｒｌｏＥｒｂａ 1 1 0ｂ。Ｐｅｒｋｉｎ -Ｅｌｍｅｒ 7Ｓｅｒｉｅｓ热分析仪 ,分温速度 1 0℃ /ｍｉ…