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聚硅氧烷键合的离子液体用作高温气相色谱固定相的研究 总被引:1,自引:0,他引:1
合成了阴离子为二(三氟甲基磺酸酰)亚胺(NTf-2)的新型聚硅氧烷键合离子液体 ([PSOMIm][NTf2]),并采用静态涂渍法,制备了毛细管气相色谱柱.该固定相具有良好的热稳定性.热重测试显示,温度高于380 ℃后,[PSOMIm][NTf2]开始缓慢分解.色谱性能评价显示,此固定相对多种异构体和同系物均具有良好的分离选择性和高的热稳定性.对Grob试剂的分离结果表明,各种组分均能在柱上得到良好的分离且峰的对称性很好.此新型聚合物离子液体在高温气相色谱固定相的研究和应用方面具有较大的潜力. 相似文献
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本工作从高聚物粘弹蛇行模型出发,结合Schallamach的橡胶摩擦理论,提出了高聚物摩擦点内耗模型,给阻尼过程以数学描述,阐述了分子链结构与互溶性对阻尼性能的影响。本工作还设计合成了几种液体聚醚的共聚物,用Rheovibron及线膨胀仪研究了它们的互溶性及阻尼性能,并对某些试样的吸振性能进行了实际振动测量和理论计算。 相似文献
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综述了端基功能化聚合物表面结构与性能的最新研究进展.聚合物端基功能化是实现聚合物表面改性的一种有效技术.通过端基功能化可以精确控制聚合物表面功能基团的种类和数量,从而影响聚合物表面的化学结构与性能.重点论述了功能化端基在聚合物表面的离析现象和产生这一现象的原因,以及功能化端基对聚合物表面分子运动能力的影响.本文还介绍了近年来用于研究端基功能化聚合物表面的表征新技术,如SFG、NR、SSIMS等.对端基功能化聚合物表面的环境响应性也进行了阐述.指出了利用不同功能化端基可以有效地控制聚合物表面的亲疏水性.并对端基功能化聚合物的应用进行了展望. 相似文献
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在1-丁基-3-甲基咪唑四氟硼酸盐离子液体中以氯化苄为引发剂,氯化亚铜/2,2’-联吡啶为催化剂成功实现了丙烯酰胺的原子转移自由基聚合(ATRP)。用IR对聚合物的结构进行了表征,证实聚合物链端具有-Cl端基。考察了引发剂用量、催化剂和配体用量、单体用量和反应时间等因素对丙烯酰胺在离子液体中的原子转移自由基聚合的影响,结果表明,反应时间为1.5 h时转化率达到31.43%,MnGPC=4451,Mw/Mn=1.38。且80 ℃下丙烯酰胺在离子液体中的最佳聚合工艺条件为:单体浓度3 mol/L,引发剂浓度0.010 mol/L,催化剂浓度0.015 mol/L,反应时间1 h。 相似文献
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J. D. Margerum F. G. Yamagishi A. M. Lackner E. Sherman L. J. Miller C. I. Van Ast 《Liquid crystals》1993,14(2):345-350
The problems of photoinitiator contamination are addressed for the liquid crystal phase in polymer dispersed liquid crystal films formed by photopolymerization induced phase separation of liquid crystal from monomer solutions. Initiator contamination lowers the clearing point of the liquid crystal phase, and decreases the photostability and resistivity of the polymer dispersed liquid crystal. These problems are minimized by replacing the conventional photoinitiators with copolymerizable initiators which become incorporated in the polymer phase as it separates. Copolymerizable photoinitiators are studied and used to form polymer dispersed liquid crystals with higher clearing point liquid crystal phases, higher resistivity, and better photostability than polymer dispersed liquid crystals formed with conventional photoinitiators. These improvements provide very significant advantages for many polymer dispersed liquid crystal applications. 相似文献
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J. D. Margerum F. G. Yamagishi A. M. Lackner E. Sherman L. J. Miller C. I. Van Ast 《Liquid crystals》2013,40(2):345-350
Abstract The problems of photoinitiator contamination are addressed for the liquid crystal phase in polymer dispersed liquid crystal films formed by photopolymerization induced phase separation of liquid crystal from monomer solutions. Initiator contamination lowers the clearing point of the liquid crystal phase, and decreases the photostability and resistivity of the polymer dispersed liquid crystal. These problems are minimized by replacing the conventional photoinitiators with copolymerizable initiators which become incorporated in the polymer phase as it separates. Copolymerizable photoinitiators are studied and used to form polymer dispersed liquid crystals with higher clearing point liquid crystal phases, higher resistivity, and better photostability than polymer dispersed liquid crystals formed with conventional photoinitiators. These improvements provide very significant advantages for many polymer dispersed liquid crystal applications. 相似文献
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以对苯二胺、3-氯丙醇和4-羟基苯甲醛为原料,合成对苯二(对苯丙氧基醇)亚胺液晶基元,再与对苯二异氰酸酯和1,3-双(3-氨基丙基)四甲基二硅氧烷反应,合成席夫碱型硅氧烷聚氨酯液晶聚合物。 通过红外光谱法、X射线衍射、热分析、偏光显微镜等技术手段对其结构和性能进行了表征。 结果表明,该物质为席夫碱有机硅聚氨酯液晶聚合物,属于近晶相液晶,液晶区间为103~150 ℃,热分解温度为300 ℃。 用席夫碱型硅氧烷聚氨酯液晶固定相制备填充色谱柱,考察固定液的相对极性及其对取代苯位置异构体的色谱分离性能。 合成的席夫碱型硅氧烷聚氨酯液晶聚合物的液晶温度范围为103~146 ℃,属于强极性固定液(Px=79),各组分色谱峰的分离度为0.96~3.33。 相似文献
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The electro-optic properties of liquid crystal devices are modified by the presence of a polymer network formed by the exposure to UV light of reactive mesogen molecules dissolved within the liquid crystal host. The effect of the polymer network depends on its density, and knowledge of this through the liquid crystal layer is necessary to understand qualitatively, and to model quantitatively, the electro-optic properties of liquid crystal devices containing polymer networks. Various techniques have been used to study the distribution of the polymer network and these show an increased concentration of the network near the surface closest to the UV light. Evidence is presented that the polymer network distribution becomes more uniform when non-UV absorbing liquid crystals are used. 相似文献
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The electro-optic properties of liquid crystal devices are modified by the presence of a polymer network formed by the exposure to UV light of reactive mesogen molecules dissolved within the liquid crystal host. The effect of the polymer network depends on its density, and knowledge of this through the liquid crystal layer is necessary to understand qualitatively, and to model quantitatively, the electro-optic properties of liquid crystal devices containing polymer networks. Various techniques have been used to study the distribution of the polymer network and these show an increased concentration of the network near the surface closest to the UV light. Evidence is presented that the polymer network distribution becomes more uniform when non-UV absorbing liquid crystals are used. 相似文献
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The structural properties of a polymer-containing ionic liquid under the conditions of good solubility of a flexible polymer
are studied theoretically. Two systems are discussed: In one, polymer solubility is due to the presence of specific interaction
between polymer chains and solvent cations; in the other, polymer solubility is due to the presence of specific interactions
between the polymer and solvent anions. The dependences of the structural characteristics of a solution on the polymer concentration
and the energy of attraction between polymer chains and solvent ions are calculated. In a semidilute polymer solution, long-range
correlations of polymer chains with a power dependence of the characteristic scale of ordering on the polymer density appear.
The conditions under which, along with the intermediate ordering typical of a pure ionic liquid, the long-range ordering of
the solvent cations and anions occur after addition of a polymer to the ionic liquid are studied. 相似文献
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作为锂离子电池重要组分,隔膜由多孔聚烯烃高分子材料组成;电解质体系由有机碳酸酯和六氟磷酸锂混合组成,虽具有高离子电导率,但因液态碳酸酯的易燃特性给锂离子电池带来了安全隐患。利用能够将液态电解质体系凝胶化的聚合物制备得到的凝胶聚合物隔膜,结合了液态电解质体系高电导率和固态电解质高安全性的优点。凝胶聚合物隔膜的研究从简单微孔凝胶聚合物隔膜开始,经历了引入少量纳米无机颗粒的掺杂凝胶聚合物隔膜,到引入大量纳米颗粒的凝胶陶瓷隔膜的发展历程。本文详细介绍这三种类型凝胶聚合物隔膜的物理化学特性,最后展望凝胶聚合物隔膜的发展趋势。 相似文献