单壁碳纳米管的分散分离及定量表征

发布时间：2018-06-02 16:16

  本文选题：单壁碳纳米管 + 分散　； 参考：《北京服装学院》2015年硕士论文

【摘要】：单壁碳纳米管（SWCNTs）自被发现以来，因其独特及优异的物理化学性质，使其在电子、复合材料、生物医学等众多领域都表现出了良好的发展前景。不同结构的SWCNTs性质不同，而目前制备手段生产出的SWCNTs均是不同手性、不同管径的混合物，对于这类混合物的分离和性能评价目前尚无适宜的方法和统一的评价标准。这种状况不仅增加了SWCNTs的质量控制难度，而且也极大地阻碍到了它的应用。本论文正是基于此目的，从SWCNTs应用的角度，对其分散与手性分离方法进行了研究；另外，为了开发适宜分离SWCNTs的凝胶色谱柱，本文还对制备壳聚糖微球色谱柱进行了探索。 （1）通过采用十二烷基硫酸钠（SDS）、脱氧胆酸钠（DOC）、胆酸钠（SC）、十二烷基苯磺酸钠（SDBS）、Tritron X-405及十六烷基三甲基溴化铵（CTMAB）六种表面活性剂对SWCNTs进行超声分散，确定了紫外-可见-近红外吸收光谱的吸光度以及共振比分别为评价SWCNTs的分散总浓度以及单分散浓度的参量。结果表明表面活性剂分散SWCNTs总浓度从高到低依次为：SDS DOC X405 SC CTMAB SDBS；SWCNTs单分散浓度从高到低依次为：DOC SC CTMAB X405 SDBS SDS。 （2）利用单根凝胶色谱技术，考察SDS、DOC、SC、SDBS及X405溶液五种流动相对SWCNTs手性分离的影响。建立了由吸收光谱结果计算的面积百分比Si,j，及面积百分比极差之和∑Rsi作为定量表征指标的方法，分别对同一流动相和不同流动相的分离效果进行评价，结果表明SDS溶液作为流动相对SWCNTs的分离效果较佳。 （3）利用单根凝胶色谱法，采用聚乙烯醇凝胶（Toyopearl）、聚丙烯酰胺凝胶(Bio Gel)作为填料对SWCNTs进行手性分离，，并与传统琼脂糖凝胶（Sepharose）、丙烯葡聚糖凝胶（Sephacryl）对比，结果表明不同凝胶对SWCNTs手性的选择性不同，Bio Gel凝胶对（8,3）、（7,5）、（10,2）手性SWCNTs选择性较好；Sephacryl凝胶对（9,4）、（7,6）、（8,4）手性SWCNTs选择性较好；Toyopearl对（8,6）手性SWCNTs选择性较好；Sepharose对（9,5）、（10,5）、（8,7）手性SWCNTs选择性较好。并根据上述结论，首次采用多种凝胶填料、多根色谱柱阶梯法（（凝胶色谱柱填料的顺序依次为：Bio Gel，Sephacry，Toyopearl，Sepharose）对SWCNTs进一步分离，可得到手性指数种类更为单一的SWCNTs。 （4）利用离心力场流仪分别对六种表面活性剂分散的SWCNTs样品进行分离，并用多角度光散射以及紫外检测器实时在线检测。通过对检测结果的分析，发现无论样品中碳纳米管的分散情况如何，均可实现不同尺寸的分离，得到了SWCNTs的各个Rg分布图。验证了此新方法对碳纳米管分离的适用性。 （5）采用乳化交联法，通过控制反应过程的搅拌速度、壳聚糖浓度、醋酸浓度以及乳化剂含量，制备了成球效果好、粒径均匀、性质稳定的壳聚糖微球。用这种微球色谱柱对SWCNTs进行分离，结果显示，由于壳聚糖微球的空间网状结构，对SWCNTs的分离效果较差，且没有有效的流动相使碳管与微球分开开来。但是，通过对壳聚糖微球-SWCNTs的表征，证明了壳聚糖微球能够大量吸附碳纳米管，且稳定性、导电性均有所增强，并保持了各自优异的性质。
[Abstract]:Since the discovery of the single wall carbon nanotube (SWCNTs), because of its unique and excellent physical and chemical properties, it has shown good prospects in many fields, such as electronics, composite materials, biomedicine and many other fields. The properties of different structures are different in the properties of SWCNTs. At present, the SWCNTs of the produced means of production is a mixture of different chiral and different pipe diameters. There is no suitable method and unified evaluation standard for the separation and performance evaluation of this kind of mixture. This situation not only increases the difficulty of the quality control of SWCNTs, but also greatly hinders its application. This paper is based on this purpose and studies the method of dispersion and chiral separation from the angle of SWCNTs application. In addition, in order to develop gel chromatographic column suitable for separation of SWCNTs, the preparation of chitosan microsphere chromatographic column was also explored.
(1) by using twelve alkyl sodium sulfate (SDS), sodium deoxycholate (DOC), sodium cholate (SC), twelve alkyl benzene sulfonate (SDBS), Tritron X-405 and sixteen alkyl three methyl ammonium bromide (CTMAB), six kinds of surfactant were used to disperse SWCNTs to determine the absorbance of ultraviolet visible near infrared absorption spectrum and the resonance ratio of SWC respectively. The total concentration of NTs and the parameters of the monodisperse concentration showed that the total SWCNTs concentration of the surfactant dispersed from high to low was SDS DOC X405 SC CTMAB SDBS, and the SWCNTs monodisperse concentration from high to low was in the order of DOC SC CTMAB.
(2) the effect of five kinds of flow relative to SWCNTs chiral separation of SDS, DOC, SC, SDBS and X405 solution was investigated by single gel chromatography. The separation efficiency of the same flow phase and the different mobile phase was established by the square method of the area percentage Si, J, the area percentage extreme difference and the sigma Rsi, calculated by the absorption spectrum. The results showed that SDS solution had better separation effect than SWCNTs.
(3) the chiral separation of SWCNTs by polyvinyl alcohol gel (Toyopearl) and polyacrylamide gel (Bio Gel) was used as a filler by single gel chromatography, and compared with the traditional agarose gel (Sepharose) and propylene dextran gel (Sephacryl), the results showed that the selectivity of different gels to SWCNTs was different, Bio Gel gel pair (8,3), 7,5 (7,5). (10,2) the selectivity of chiral SWCNTs is better; Sephacryl gel has good selectivity to (9,4), (7,6), (8,4) chiral SWCNTs, Toyopearl to (8,6) chiral SWCNTs is better, Sepharose pairs (9,5), and chiral selectivity is better. And according to the above conclusion, the first kind of gel filler, multi column chromatography (gel chromatography) The sequence of column packing is: Bio Gel, Sephacry, Toyopearl, Sepharose). Further separation of SWCNTs can result in a single SWCNTs. with a more chiral index.
(4) separate the SWCNTs samples of six kinds of surfactant by centrifugal force field flow meter, and use multi angle light scattering and UV detector on line detection. Through the analysis of the detection results, it is found that the dispersion of carbon nanotubes in the samples can be separated in different sizes, and each SWCNTs can be obtained. The Rg distribution map verified the applicability of the new method to the separation of carbon nanotubes.
(5) by controlling the mixing rate of the reaction process, the concentration of chitosan, the concentration of acetic acid and the content of emulsifier, the chitosan microspheres with good ball effect, uniform particle size and stable properties were prepared by emulsifying crosslinking method. The SWCNTs was separated by this microsphere column. The results showed that the space network structure of chitosan microspheres was used for SWCNTs The separation effect is poor, and there is no effective mobile phase to separate the carbon nanotubes from the microspheres. However, the chitosan microspheres have been characterized by the characterization of the chitosan microspheres -SWCNTs. It is proved that the chitosan microspheres can adsorb a large number of carbon nanotubes, and the stability and electrical conductivity are enhanced, and their excellent properties are maintained.
【学位授予单位】：北京服装学院
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TB383.1

【参考文献】

相关期刊论文 前1条

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