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C60接枝聚(N-乙烯基咔唑)的合成、表征及光电导性能 总被引:2,自引:0,他引:2
自从C60被发现和被制备出来以后,其特殊的结构和独特的物理和化学性质受到各研究领域学者的广泛青睐.聚(N-乙烯基咔唑)(PVK)体系经 C60掺杂后光电导性能有很大幅度提高.但掺杂体系不稳定,因而限制了对该类材料的应用.为了克服这种缺点,我们尝试用各种简单的方法把C60化学键合到高分子链中,制备具有光电导性能的C60高分子衍生物. 最近,唐本忠[1]和 Patil[2]等分别用常规的自由基聚合方法,将C60接枝到聚合物分子主链上,我们已研究了不含导电高分子的C60共聚物的光电导性能[3],本文采用… 相似文献
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以聚丙烯腈为原料,首先通过部分腈基的[3+2]合环反应转化为聚(乙烯基四唑-co-丙烯腈)[Poly(VT-co-AN)],再通过碱性水解反应将剩余的腈基转化为羧基,合成出聚(乙烯基四唑-co-丙烯酸)[Poly(VT-co-AA)]。 采用傅里叶红外变换光谱仪(FT-IR)、核磁共振碳谱仪(13C NMR)、酸碱滴定等方法对Poly(VT-co-AN)和[Poly(VT-co-AA)的结构进行了表征,结果表明,Poly(VT-co-AN)的分子链中含有腈基、四唑基团和部分羧基,四唑基团的含量为68.6%,与酸碱滴定法测定的四唑基团的含量相近,[Poly(VT-co-AA)中含有四唑基团和羧基,不含有腈基,酸值高于Poly(VT-co-AN),四唑基团的含量为67.6%,与叠氮化钠与聚丙烯腈的摩尔比相近。 热失重分析结果显示[Poly(VT-co-AA)的热分解速率加快,在270~285 ℃的温度区间内分解完全。 相似文献
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用原子转移自由基聚合(ATRP)法合成了结构可控的三嵌段共聚物聚(4-乙烯基吡啶)-b-聚环氧乙烷-b-聚(4-乙烯基吡啶)(P4VP-b-PEO-b-P4VP).用核磁共振氢谱和凝胶渗透色谱对该共聚物进行了表征;将该共聚物作为毛细管物理吸附涂层,用毛细管电泳对碱性混合蛋白质进行了分离.结果表明:蛋白质的分离效率随着P... 相似文献
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研究了肉桂酸、肉桂酸乙酯经UV光照后的低温燐光性质,在1mol/L HClk中UV光照使其反式异构化为顺式,烧光分别增强5与10倍。加碱碱化后燐光进一步增强2与5倍。讨论了两药燐光产生的机制,建立了低温燐光分析法,检出限分别为75与110μg/L。 相似文献
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利用NMR技术研究了聚乙二醇-b-聚(4-乙烯基吡啶)(PEG114-b-P4VP107)和聚(N-异丙烯基丙烯酰胺)-b-聚(4-乙烯基吡啶)(PNIPAM53-b-P4VP260)在逐步降低聚(4-乙烯基吡啶)链段质子化程度时嵌段共聚物的胶束化过程.在开始形成胶束时,吡啶环上氢原子的自旋-晶格弛豫时间(T1)急剧减小.结果表明,PEG114-b-P4VP107在质子化程度降为0.54时已有胶束生成;PNIPAM53-b-P4VP260在质子化程度降为0.58时也能观测到胶束生成的信号.将两个嵌段共聚物各自制得胶束的溶液相混合,观测到了发生在高分子链间的2D NOE信号,这表明所制得溶液中胶束与高分子链间有链交换的动态平衡. 相似文献
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<正> Bulk polymerization of vinylene carbonate using t-butylperoxypivalate at 40℃gave colourless, high molecular weight poly(vinylene carbonate) (PVCA). Solutions of PVCA in acetone and DMF are not stable at 25℃and this degradation was studied. From measurements in DMF with unfractionated PVCA a Mark-Houwink equation was obtained: 相似文献
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The applicability of two non-parametric extrapolation methods to FT-IR absorptance spectra is investigated. The first method minimizes those parts of the spectrum which do not satisfy a given constraint, while the second one changes them in each iteration through the true values. 相似文献
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The relationships between resolution, stability, pseudopotential well depth, acceptance aperture, and transmission for sinusoidal quadrupole mass filters are examined graphically and mathematically. Simple linear or power relationships are revealed. Comparison of these quantities plotted against resolving power show that the pseudopotential well depth correlates well with the mass filter transmission. Pseudopotential well depth is directly proportional to the product of dimensionless stability well depth and the AC voltage. This relationship extends to all quadrupoles regardless of operational zone because it is rooted in stability. Ion transmission and sensitivity scale directly with the pseudopotential well depth. Resolving power and pseudopotential well depth increase when operating in higher stability zones for all types of mass filters. Unfortunately, for fixed frequency sine wave mass filters, the increased resolving power and pseudopotential well depth are accompanied by a significant reduction of the mass range and increased in fringe field effects. For these reasons, sine mass filter operation in higher stability zones has been reported but not commercially produced. In contrast, for rectangular wave mass filter operation, there is no mass range limitation in any stability zone. The fringe field does not increase because the AC voltage is constant and does not change within a single stability zone or between them. A DC voltage is also unnecessary to access any zone. The high resolution and sensitivity of rectangular wave mass filters that can be gained by operation in higher stability zones without mass limit and limited fringe field restrictions suggest a bright and expansive future for this technology. 相似文献
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研究了微波协同大孔树脂催化合成肉桂酸正戊酯和异戊酯的扩大实验。结果显示,合成肉桂酸正戊酯的优化工艺条件为:肉桂酸7.4g,正戊醇17mL,CAT-600大孔树脂6.4g,微波功率400W,反应时间为8min时,酯化率97.23%;合成肉桂酸异戊酯的优化工艺条件为:肉桂酸7.4g,异戊醇19mL,CAT-600大孔树脂8.1g,微波功率700W,反应时间为8min时,酯化率97.01%。 相似文献
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研究了微波协同大孔树脂催化合成肉桂酸正丙酯和异丁酯的扩大实验。结果表明,合成肉桂酸正丙酯的优化工艺条件为:肉桂酸7.4g,正丙醇19mL,CAT-600大孔树脂6.8g,微波功率400W,反应时间为25min,酯化率92.89%;合成肉桂酸异丁酯的优化工艺条件为:肉桂酸10g,异丁醇45mL,NKC-9大孔树脂14g,微波功率600W,反应时间为35min,酯化率90.18%。 相似文献
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Jiulin Xia Paul L. Dubin Shun Edwards Henry Havel 《Journal of Polymer Science.Polymer Physics》1995,33(7):1117-1122
MW fractions of poly(dimethyldiallylammonium chloride) (PDMDAAC) were prepared by preparative size-exclusion chromatography and characterized by static and dynamic light scattering, viscometry, size-exclusion chromatography, and electrophoretic light scattering, in 0.50M NaCl solution. The behavior of fractions with MW < 2 × 105 was as expected for a strong polyelectrolyte in a good solvent, with a Mark-Houwink exponent of ca. 0.8, and MW-dependencies of the hydrodynamic radius and the radius of gyration of corresponding magnitude. At higher MW, curvature appears in the MW-dependencies, which can be best explained by the presence of branching. While this notably lowers the intrinsic viscosity at high MW, the electrophoretic mobility is unchanged regardless of molar mass. Thus, the branched polymers display the electrophoretic free-draining behavior characteristic of linear polyelectrolytes. ©1995 John Wiley & Sons, Inc. 相似文献
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用简易GPC柱研究了在未知合适的Mark-Houwink 系数的情况下,通过GPC和特性粘度的数据,同时计算出宽分布硅烷亚芳弹性体聚合物的分子量和这种类型聚合物的 Mark-Houwink 系数的方法。装柱填料为多孔硅胶球,理论塔板数 4200—5500块/米以上,塔板高度 0.7—0.9毫米。其分子量分布宽度指数在2左右。素炼后,分子量分布变窄,分子量下降。 相似文献
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环氧丙烷-三氯化铁、环氧氯丙烷-二乙基氯化铝和铝卟啉-环氧氯丙烷体系是合成分子量为10~4数量级晶态和10~5数量级非晶态聚环氧氯丙烷的比较理想的体系。利用合成产物的分级试样确定了非晶态聚环氧氯丙烷的Mark-Houwink方程。 相似文献
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M. A. S. Carvalho Filho N. S. Fernandes M. I. G. Leles R. Mendes M. Ionashiro 《Journal of Thermal Analysis and Calorimetry》2000,59(3):669-674
Some new compounds of cinnamic acid with lighter trivalent lanthanides were prepared in the solid state. The compounds have
general formula ML3 H2 O, where L is cinnamate (C6 H5 –CH=CH–COO– ) and M is La, Ce, Pr, Nd or Sm. Thermogravimetry, derivative thermogravimetry, differential scanning calorimetry, infrared absorption
spectra and X-ray diffraction powder patterns were used to characterize and to study the thermal stability and thermal decomposition
of these compounds.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献