共查询到19条相似文献,搜索用时 416 毫秒
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热致液晶高分子(TLCP)是一类重要的特种工程塑料,在航空航天、军事和电子电气等领域有着广泛的应用。本文简要介绍了TLCP的发展历程,综述了热致液晶高分子的发展现状;对热致液晶高分子的性能、合成方法、分类以及应用作了重点阐述,并对其发展提出展望。 相似文献
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阐述了高分子液晶的形成条件,综述了纤维素液晶、甲壳素液晶、铁电液晶、盘状液晶、卤代液晶等五种新型高分子液晶材料的结构、性能及其应用前景,并对高分子液晶的发展方向进行了展望。 相似文献
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液晶高分子的分子设计 总被引:1,自引:0,他引:1
简单介绍了液晶高分子的结构特点,分类及其应用状况,详细介绍了主链型和侧链型液晶高分子设计的新进展,根据溶臻主链型液晶高分子和热臻主链型液晶高分子分子结构的不同,提出今后设计主链液晶高分子的主要任务,从主链结构,液晶基元类型和柔性间隔出发介绍了侧链液晶高分子分子设计的关键,最后介绍了液晶高分子分子设计的发展趋势。 相似文献
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向列型含氟侧链高分子液晶的合成与表征 总被引:1,自引:0,他引:1
合成了4-(丙烯酸乙氧基酯)苯甲酸,4-(丙烯酸乙氧基酯)苯甲酰氧基苯甲酸等系列液晶中间体.首次合成了4-(丙烯酸乙氧基酯)苯甲酰氧基苯甲酸基元的含氟侧链高分子液晶,采用IR,1HNMR和19FNMR表征了其分子结构.通过DSC分析和偏光显微镜研究了含氟侧链高分子液晶的织构形态.结果表明,4-(丙烯酸乙氧基酯)苯甲酰氧基苯甲酸基元含氟侧链高分子液晶具有向列型液晶的织构形态.4-(丙烯酸乙氧基酯)苯甲酰氧基苯甲酸基元含氟侧链高分子液晶,其液晶温度范围较宽,随着液晶基元成分的降低,含氟侧链成分的增加,高分子液晶玻璃化温度略有降低. 相似文献
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The objective of this work has been to study composite systems in which carbon fibers are dispersed in a liquid crystal polymer matrix. The fundamental point of interest here has been the interfacial response that fiber surfaces can potentially induce in self-ordering polymers. The matrix material used was a thermotropic liquid crystal polyester synthesized in our laboratory from the monomers p-acetoxybenzoic acid, diacetoxyhydroquinone, and pimelic acid. The aromatic-aliphatic polymer was characterized by NMR as a chemically disordered polymer of the three structural units which exhibits a nematic phase at temperatures above 150°C. Breadline proton NMR above the solid to liquid crystal transition was used to measure the rate of magnetic alignment of molecules in the matrix and polarized optical microscopy was used to analyze interfacial zones in composite samples. Fiber surfaces were found to influence the orientation and orientational dynamics of a liquid crystal polymer matrix. This was revealed by enhanced rates of magnetic orientation in the polymer melt when carbon fibers are dispersed in the medium. Fiber surfaces were also found to stabilize nematic ordering of the polymer as the melt was heated towards complete isotropization. The phenomena discovered here may originate in the development of zones around fibers with a common molecular orientation anchored by the carbon surface. 相似文献
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收集了2010年7月~2011年6月世界塑料工业的相关资料,介绍了2010~2011年世界塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况。按通用热塑性树脂(聚乙烯、聚丙烯、聚氯乙烯、聚苯乙烯、ABS树脂),工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚),特种工程塑料(聚苯硫醚、液晶聚合物、聚醚醚酮),通用热固性树脂(酚醛、不饱和聚酯树脂、环氧树脂、聚氨酯)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍。 相似文献
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A novel liquid crystalline polyester–polyurethane (LCPU) that contains polyester mesogenic units was synthesized in the present work. Through a careful investigation of the structure and morphology of the LCPU, it was found that the home‐synthesized LCPU is a highly birefringent thermotropic nematic liquid crystal. After being blended with bisphenol‐A epoxy, the liquid crystalline polymer can, simultaneously, improve the impact strength and the glass transition temperature as well as the tensile strength and the tensile modulus of the blends. It was proved to be an efficient toughening agent for epoxy without the expense of other properties. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 783–787, 2003 相似文献
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The textural and electrooptical behavior of a nematic liquid crystal (LC) dispersed in a flexible and rigid polyester was studied. The dispersion of LC in the polymer matrix and light transmission through the polymer‐dispersed liquid crystal (PDLC) is governed by the nature of the polymer, its molecular weight, and the applied voltage. It was observed that the transmission of light and the dispersion of LC maximizes their respective values at the minimum molecular weight irrespective of the nature of the polymer and at the maximum voltage. The reason is the predominance of chain alignment over entanglement at the minimum molecular weight. As molecular weight increases, the transmission of light as well as the dispersion of LC in the polymer may increase or decrease depending on the predominance of chain entanglement or chain alignment. The alignment of LC droplets in the direction of the applied voltage is increased by an increase in the applied voltage, causing enhancement of the light transmission. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 284–289, 2003 相似文献
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介绍1991~1992年国外塑料工业进展。提供了美国、日本、原联邦德国、原苏联、法国、意大利、英国等生产国及亚洲、西欧(全部共同市场国家加奥地利、芬兰、挪成、瑞士和瑞典)、东欧、北美、中南美、非洲和大洋州等地域的塑料材料产量;按通用热塑性树脂(包括聚乙烯、聚丙烯、聚苯乙烯、ABS和聚氯乙烯)、工程塑料(包括尼龙、聚碳酸酯、热塑性聚酯、聚甲醛和改性PPO/PPE)、热固性树脂(包括酚醛、聚氨酯、不饱和聚酯和环氧树脂)、特种工程塑料(包括聚苯硫醚、液晶聚合物、聚醚砜、聚醚醚酮和聚芳酯)和其他(包括氟树脂、硅树脂和丙烯酸树脂)等,对树脂消费、合成工艺、产品应用开发、树脂品种延伸等进展作了详细介绍。 相似文献
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介绍了聚酯聚合物多元醇以及大分子分散剂端羟基预聚体、巯基改性聚酯多元醇和顺丁烯二酸酐(MA)改性聚酯多元醇的制备方法,对合成聚酯聚合物多元醇所需的原料提出了具体要求。聚酯聚合物多元醇用于制备聚氨酯软质泡沫具有一定的价格优势。 相似文献
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