CNTs的表面修饰及其在EP纳米复合材料中应用的研究进展

介绍近年来碳纳米管(CNTs)的有机表面修饰研究进展。通过对CNTs的表面修饰可改善CNTs在有机溶剂中的溶解性及在聚合物基体中的分散性。综述了CNTs改性环氧树脂(EP)纳米复合材料的研究现状,并对今后CNTs改性纳米复合材料的发展方向进行了展望。     

血催化鲁米诺化学发光性能的研究

采用荧光分光光度法,建立了血催化过氧化氢氧化鲁米诺的化学发光体系。考察了缓冲体系、pH值、血液浓度等对鲁米诺化学发光性能的影响。结果表明,当采用56.60mmol·L^-1 Na2CO3-NaHCO3缓冲体系与30.0mmol·L^-1 H2O2溶液（B液）混合时,在pH=8.98的条件下,血液浓度越高,血催化鲁米诺化学发光性能越好。     

水体中微量铁的化学发光法测定

<正> 由化学反应提供能量而导致的光辐射现象称为化学发光。以化学发光为基础的分析方法具有设备简单、灵敏度高和线性响应范围宽等优点。人们曾用鲁米诺-H_2O_2-Fe~(2+)及鲁米诺-胺-Fe~(3+) 发光体系来测定铁,但上述方法或是检出限受限制,或是Cr~(3+)、Co~(2+)、Mn~(2+)和Cu~(2+)等离子有较大的干扰。本文工作主要是采用鲁米诺-OH~--H_2O_2-Fe~(3+)化学发光体系来选择测定铁的条件,以改善方法的灵敏度和选择性。本方法应用于实际水样中铁的测定,结果满意。     

鲁米诺-十二烷基磺酸钠-高锰酸根化学发光反应的研究及其分析应用

<正> 鲁米诺(3-氨基邻苯二甲酰肼),是一种常用的化学发光反应试剂,它和氧化剂反应可产生最大发射波长为425 nm左右的化学发光。本文报道碱性介质中的鲁米诺,在阴离子表面活性剂十二烷基磺酸钠(SDS)存在时,与高锰酸根(MnO_4~-)间的化学发光反应,就反应试剂的浓度、反应液体积及碱性介     

N-(4-氨基丁基)-N-(乙基异鲁米诺)/血红素/金纳米三功能化氧化石墨烯材料的合成及性质研究

基于发光试剂N-(4-氨基丁基)-N-(乙基异鲁米诺)(ABEI),发光试剂催化剂氯化血红素(hemin)、金纳米粒子(Au NPs)和氧化石墨烯(GO)之间的非化学键作用合成了一种三功能化氧化石墨烯发光功能化复合材料。采用化学发光试剂ABEI作为还原剂,还原氯金酸在石墨烯表面合成了金纳米粒子,ABEI和hemin催化剂通过非化学键作用积聚在石墨烯表面。三功能化的石墨烯复合材料不仅具有良好的化学发光性能、良好的溶解性和水溶液的稳定性,而且为金纳米粒子为生物大分子提供了结合位点。     

固相萃取-流动注射-化学发光法测定鸡饲料和鸡肉中的氯霉素

基于氯霉素与铬(Ⅵ)的氧化-还原反应所产生的铬(Ⅲ)催化Luminol(鲁米诺)-过氧化氢化学发光体系的研究,样品中氯霉素采用液乙酸乙酯提取,固相萃取净化,结合流动注射技术和化学发光检测,建立了一种高灵敏度的快速测定鸡饲料和鸡肉中氯霉素的新方法。方法线性范围为0.03～5mg/mL和0.04～5μg/mL,方法检出限为0.03mg/kg和0.05μg/kg,平均回收率>75%,RSD为11.2%和15.4%(饲料:2.0mg/kg;鸡肉:0.5μg/kg,n=11)。     

一种固定化黄嘌呤氧化酶的制备与性能评价

为了使黄嘌呤氧化酶(XOD)可回收且能够长时间多次使用,该研究以色谱级硅球(SiO_2)为载体,采用共价键合的方式用碳纳米管(CNTs)对硅球进行包裹,并将XOD在碳纳米管包裹的硅胶球上进行固定,制备了一种以碳纳米管为介质的固定化黄嘌呤氧化酶(XOD@CNTs@SiO_2)。采用TEM和FTIR对固定化酶进行表面形貌和反应基团变化的表征;以产物尿酸为指标进行相对酶活性的评价;采用Bradford法对载体的担载量进行评价。结果表明,硅球表面经CNTs包裹后,XOD的担载量和相对酶活性分别提高2倍和2.6倍。XOD@CNTs@SiO_2在60℃储存时,储存时间至400 min后,活性仍能保持至最初的80%。4℃避光保存时,第11 d时相对活性仍为60%~70%。室温反应,连续使用至9次时,XOD@CNTs@SiO_2-30的相对酶活性仍能保留66.1%。     

鲁米诺-过氧化氢体系对敌敌畏的检测分析

通过化学发光（CL）技术，基于碱性鲁米诺－H2O2体系与敌敌畏的反应，直接对敌敌畏进行检测，并对反应条件进行优化。为有机磷农药的检测提供方便、可靠的分析方法。     

超支化聚合物共价修饰碳纳米管的制备及应用研究

碳纳米管(CNTs)具有很多优良性能,但由于在聚合物基体分散性差,限制了其广泛应用。超支化聚合物是高度支化的大分子,具有低黏度、高溶解性及含有大量末端基团等特点。利用超支化聚合物共价修饰CNTs,不仅可以提高CNTs在聚合物基体中的分散性,还能使CNTs拥有新的功能。介绍了超支化聚合物共价修饰CNTs的方法,探讨了其在生物医学、纳米材料等方面的应用前景,最后对超支化聚合物共价修饰CNTs的发展提出了建议。     

PBT/CNTs复合材料的挤出工艺与电性能

采用熔融共混方法制备聚对苯二甲酸丁二醇酯(PBT)/碳纳米管(CNTs)复合材料,通过单螺杆挤出机挤出,并对PBT/CNTs复合材料挤出工艺参数和电学性能进行研究.利用扫描电镜(SEM)从微观角度对PBT/CNTs复合材料进行观察与分析,通过对材料表面电阻率(ρs)的测定发现:随着多壁碳纳米管含量的不断增加,复合材料的表面电阻率呈不断下降趋势,250℃挤出时碳纳米管(CNTs)含量3％为复合材料的导电阈值.     

KOH-浸渍-还原法在炭纤维表面制备不同金属纳米催化剂涂层及其应用

为了催化炭纤维原位生长纳米炭纤维／纳米碳管，研究纳米炭纤维／纳米碳管在炭／炭复合材料中的应用，采用KOH-浸渍-还原法在炭纤维上制备纳米催化剂颗粒。首先用KOH处理炭纤维改变其形貌，然后将炭纤维分别在硝酸钴和硝酸镍催化剂前驱体溶液中浸渍，干燥，再用H2气还原制得催化剂颗粒，最后催化热解CO在炭纤维上原位生长纳米炭纤维／纳米碳管。结果表明：KOH处理能使炭纤维表面变得凹凸不平，有效的阻止了催化剂前驱体液体的流动，使涂层均匀；浸渍-还原法能获得粒径小、均匀、适合纳米炭纤维生长的金属颗粒；与Co纳米颗粒相比，Ni分散效果和催化效果更好。     

Effect of polymer chain length on the solubility of polystyrene grafted single‐walled carbon nanotubes in tetrahydrofuran

BACKGROUND: While carbon nanotubes are highly interesting materials for a variety of applications, their inherent insolubility limits widespread applications and solution‐phase processing. It is known that chemical functionalization can overcome this insolubility problem, and covalent grafting of polymers to the nanotube surface has been shown to be effective. In this study, the effect of polymer molecular weight on the solubility of polymer–nanotube conjugates was investigated. RESULTS: A series of nitroxide‐capped polystyrene polymers ranging in molecular weight from 2900 to 105 000 g mol^?1 were grafted to single‐walled carbon nanotubes (SWNTs). The resulting polystyrene–SWNT conjugates exhibited different degrees of solubility in tetrahydrofuran. Subsequent thermogravimetric and UV‐visible spectroscopy analyses indicated that carbon nanotube solubility reached a maximum when a polymer sample with a weight‐average molecular weight of 10 000 g mol^?1 was used. Higher and lower molecular weights resulted in reduced solubilities. CONCLUSION: Polymer chains of intermediate length maximize SWNT solubility, while lengths that are too low or too high seem to diminish the ability of the polymer–SWNT conjugates to remain in solution. Copyright © 2008 Society of Chemical Industry     

乙二胺修饰的碳纳米管对环氧树脂力学性能的影响

利用乙二胺对多壁碳纳米管(MWNTs)进行化学修饰,并制备碳纳米管/环氧树脂复合材料,研究了乙二胺修饰的碳纳米管对碳纳米管/环氧树脂复合材料力学性能的影响。实验表明,碳纳米管经乙二胺修饰后,改善了它在环氧树脂中的分散性,提高了环氧树脂复合材料的力学性能。氨基化碳纳米管用量达1.0%时,复合材料的冲击强度、断裂伸长率、拉伸强度和弯曲强度分别较纯环氧树脂提高200%、275%、48%和30%。     

Functionalized carbon nanotubes: properties and applications

Carbon nanotubes can be functionalized via amidation and esterification of the nanotube-bound carboxylic acids. The solubility of these functionalized carbon nanotubes makes it possible to characterize and study the properties of carbon nanotubes using solution-based techniques. Representative results concerning the solubility, dispersion, defunctionalization, and optical properties of the functionalized carbon nanotubes are presented. Several examples for the use of functionalized carbon nanotubes in the fabrication of polymeric carbon nanocomposites, the probing of nanotube-molecule interactions, and the conjugation with biological species are highlighted and discussed.     

Chemistry of single-walled carbon nanotubes

In this Account we highlight the experimental evidence in favor of our view that carbon nanotubes should be considered as a new macromolecular form of carbon with unique properties and with great potential for practical applications. We show that carbon nanotubes may take on properties that are normally associated with molecular species, such as solubility in organic solvents, solution-based chemical transformations, chromatography, and spectroscopy. It is already clear that the nascent field of nanotube chemistry will rival that of the fullerenes.     

Thin-walled carbon nanotubes grown using a zirconium catalyst

Thin-walled carbon nanotubes (TWCNTs) were synthesized using a zirconium (Zr) plate by cold-wall chemical vapor deposition of a mixture gas consisting of C₂H₂ and H₂ under a pressure of 1.20 torr. The Zr plate was used for the formation of Zr nanocatalysts during the thermal process and used as substrate to eliminate the effects of interactions between catalyst and substrate during CNT synthesis. The TWCNTs were 4-9 nm in diameter and a few micrometers long. Nanometer-sized defects on the Zr bulk material may have a low melting temperature, allowing them to form droplet-like catalysts and achieve high carbon solubility for the formation of CNTs.     

Coiled carbon nanotubes growth via reduced-pressure catalytic chemical vapor deposition

Coiled carbon nanotubes were prepared by catalytic chemical vapor deposition (CCVD) on finely divided Co nano-particles supported on silica gel under reduced pressure and relatively low gas flow rates. The morphology and the graphitization of the coil tube, coil bend, and coil node of the coiled carbon nanotubes were examined by transmission electron microscope (TEM). The influence of pH value, reaction pressure, and flow rate of C₂H₂ on the growth of the coiled carbon nanotubes were also discussed. With the drastic reduction in the consumption of C₂H₂ and lower required pressure with the modified CCVD approach, the amount of amorphous carbon coated on the carbon nanotubes was shown to be greatly reduced. Most importantly, this method offers a preferable alternative for the efficient, environment-friendly and safer growth of coiled carbon nanotubes.     

Improvement single-wall carbon nanotubes (SWCNTs) based on functionalizing with monomers 2-hydroxyethylmethacryate (HEMA) and N-vinylpyrrolidone (NVP) for pharmaceutical applications as cancer therapy

The functionalized carbon nanotubes play significant roles in the fields such as preparation of composite materials and biological technologies. This paper explains the covalent functionalization of single-wall carbon nanotubes (SWCNTs) with biomedical important monomers, 2-hydroxyethylmethacryate (HEMA) and N-vinylpyrrolidone (NVP) by chemical grafting of HEMA and PVP monomers via free radical polymerization. To get carboxylic acid functionalized SWCNTs, first the nanotubes were oxidized with a mixture of nitric acid and sulfuric acid (1:3). Then, the binding of HEMA and NVP onto the surface of SWCNTs was performed by chemical functionalization of HEMA, NVP with acid chloride-bound carbon nanotube by esterification reaction. These results were confirmed by FT-IR and SEM. The cell culture experiments conducted for pharmaceutical applications were used as cancer therapy.     

碳纳米管改性聚脲材料的研究

制备了化学改性的碳纳米管,并用喷涂制样的方式制备了碳纳米管改性的聚脲材料。研究了碳纳米管的种类和添加量等因素对聚脲力学性能的影响。结果表明,涂膜的拉伸强度和撕裂强度随着原始碳纳米管含量的增多而降低;而随着改性碳纳米管添加量的增加,涂膜拉伸强度先升高后下降,撕裂强度提高,断裂伸长率降低;且改性单壁碳纳米管对聚脲材料力学性能的增强效果明显优于改性双壁和多壁碳纳米管的。