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1.
采用新方法合成了meso-四(4-酰肼基苯基)卟啉及其金属配合物, 通过化学键将酰肼卟啉上的酰肼基与活化的多壁碳纳米管(MWNTs)发生酰胺化反应, 从而得到卟啉共价化学修饰的多壁碳纳米管复合物; 利用卟啉环上的π电子与多壁碳纳米管管壁上的π电子通过π-π堆积效应, 得到卟啉非共价化学修饰的碳纳米管复合物. 通过红外光谱、紫外和荧光光谱对比分析, 发现在卟啉与碳纳米管间存在强烈的电子效应, 且非共价修饰的卟啉-碳纳米管复合物的荧光猝灭率更高.  相似文献   

2.
合成了5-(4-羟基苯基)-10,15,20-三苯基卟啉锌配合物,与活化的多壁碳纳米管(MWNT)发生酯化反应,从而得到金属卟啉有机共价化学修饰的多壁碳纳米管复合物;利用金属卟啉环上的π电子与多壁碳纳米管管壁上的π电子通过π-π堆积效应,得到金属卟啉有机非共价修饰的多壁碳纳米管复合物.通过透射电镜(TEM)考察了金属卟啉-多壁碳纳米管复合物的形貌特征;通过红外光谱对产物的化学结构进行了表征;通过紫外光谱、荧光光谱和热失重分析(TGA)对比分析了两类复合物,发现非共价修饰的金属卟啉-碳纳米管复合物的荧光淬灭率更高,非共价修饰的金属卟啉-碳纳米管复合物中卟啉的含量比较高.  相似文献   

3.
合成了5-(4-羟基苯基)-10,15,20-三苯基卟啉锌配合物, 与活化的多壁碳纳米管(MWNT)发生酯化反应, 从而得到金属卟啉有机共价化学修饰的多壁碳纳米管复合物; 利用金属卟啉环上的π电子与多壁碳纳米管管壁上的π电子通过π-π堆积效应, 得到金属卟啉有机非共价修饰的多壁碳纳米管复合物. 通过透射电镜(TEM)考察了金属卟啉-多壁碳纳米管复合物的形貌特征; 通过红外光谱对产物的化学结构进行了表征; 通过紫外光谱、荧光光谱和热失重分析(TGA)对比分析了两类复合物, 发现非共价修饰的金属卟啉-碳纳米管复合物的荧光淬灭率更高, 非共价修饰的金属卟啉-碳纳米管复合物中卟啉的含量比较高.  相似文献   

4.
合成了meso-四(4-磺酸钠苯基)卟啉及其Zn, Cu, Mn配合物, 通过共价与非共价的方法将其分别修饰到多壁碳纳米管上. 采用红外光谱对产物结构进行表征|通过透射电镜(TEM)考察了卟啉-多壁碳纳米管复合物的形貌特征|通过紫外光谱、荧光光谱对比分析了两类复合物, 发现在卟啉与多壁碳纳米管之间存在较强的电子效应, 同时发现非共价修饰的卟啉-碳纳米管复合物的荧光淬灭率更高|热重分析(TGA)表明非共价的卟啉-碳纳米管复合物中卟啉的含量比较高. 对修饰后的复合物进行了溶解性测试, 结果表明共价修饰的复合物在水中有较好的溶解性和分散性.  相似文献   

5.
卟啉和酞菁修饰的单壁碳纳米管的合成及光谱性质   总被引:1,自引:0,他引:1  
利用5-(4-氨基苯基)-10,15,20-三(3,5-二辛氧基苯基)卟啉和2,9,16-三叔丁基-23-氨基锌(Ⅱ)酞菁通过酰胺键连接方式同时对单壁碳纳米管进行共价修饰, 通过红外光谱、拉曼光谱、X射线光电子能谱和透射电镜对所得碳纳米管复合物进行了表征, 证实了其结构. 紫外-可见吸收光谱和荧光光谱分析表明, 光活性分子卟啉和酞菁均与单壁碳纳米管之间存在较强的电子效应. 经卟啉和酞菁共同修饰的单壁碳纳米管复合物比卟啉和酞菁单独修饰的碳纳米管复合物的吸光范围更宽, 而且分散性较好(309 mg/L), 是潜在的光电转换材料.  相似文献   

6.
以多壁碳纳米管为基板,运用简单磁力搅拌方法,通过π-π堆积作用,使1,4-二氨基蒽醌负载于多壁碳纳米管材料上,获得了聚氨基蒽醌/多壁碳纳米管复合物(PDAAQ/MWCNTs)。采用傅立叶红外光谱(FTIR)、透射电子显微镜(TEM)、循环伏安(CV)和恒流充放电(GCD)等方法对PDAAQ/MWCNTs的结构和性能进行表征。结果发现3~4 nm厚的聚氨基蒽醌层原位生长在多壁碳纳米管上,这种独特的结构极大地增加了复合物的比表面积和聚氨基蒽醌的利用率。分散性能好的PDAAQ/MWCNTs复合物具有高的赝容性能。  相似文献   

7.
制备了改性多壁碳纳米管/聚乳酸复合材料,研究了改性多壁碳纳米管对聚乳酸的增强作用.通过拉曼光谱分析、热重分析证实了多壁碳纳米管酸化酯化反应的发生.通过溶液法制备了聚乳酸/改性多壁碳纳米管复合物.考察了聚乳酸和改性多壁碳纳米管复合体系的相容性.扫描电镜分析结果说明了聚乳酸和改性多壁碳纳米管复合物相容性的变化.随着改性多壁碳纳米管在复合物中含量的增加,体系的分散效果也越好,相容性也有提高.实验结果表明,在聚乳酸材料中添加改性碳纳米管材料到一定值对,可以提高材料的力学性能,且当改性碳纳米管添加量达到1.5%的时候材料力学性能达到了一个最大值,拉伸强度可达120.4MPa.  相似文献   

8.
以多壁碳纳米管(MWNTs)为原料,经自由基反应,制备了氰基改性的多壁碳纳米管,然后采用Al-NiCl2.6H2O-THF体系还原氰基得到了氨基化的碳纳米管。通过拉曼光谱仪、热重分析仪、X射线光电子能谱仪和透射电子显微镜对产物的结构与形貌进行了表征。结果表明:氨基通过共价键枝接在MWNTs的表面,氨基化多壁碳纳米管每1000个表面碳原子中有17.1个转化为氨基;该反应条件温和,反应时间短,且不破坏MWNTs的结构。  相似文献   

9.
高性能环氧树脂/碳纳米管复合物的热分析研究   总被引:2,自引:0,他引:2  
用差示扫描量热仪(DSC)、热失重分析仪(TGA)和动态力学热分析仪(DMTA)研究了多壁碳纳米管(MWNTs)/高性能4,4′-二氨基二苯甲烷四缩水甘油环氧树脂(TGDDM)/4,4′-二氨基二苯基砜(DDS)复合物的热性能.Kissinger和Flynn-Wall-Ozawa的非等温固化动力学研究发现,随着MWNTs含量的增加,复合物固化反应的活化能先减小后增大.TGA研究表明,MWNTs的添加对环氧树脂热稳定性影响很小.碳纳米管填充到TGDDM/DDS体系后,复合物的储存模量随着MWNTs含量的增加而增大,而玻璃化温度却随之减小.  相似文献   

10.
以多壁碳纳米管(MWNTs)为原料, 经自由基反应, 制备了氰基改性的多壁碳纳米管, 然后采用Al-NiCl2·6H2O-THF体系还原氰基得到了氨基化的碳纳米管。通过拉曼光谱仪、热重分析仪、X射线光电子能谱仪和透射电子显微镜对产物的结构与形貌进行了表征。结果表明:氨基通过共价键枝接在MWNTs的表面, 氨基化多壁碳纳米管每1000个表面碳原子中有17.1个转化为氨基;该反应条件温和, 反应时间短, 且不破坏MWNTs的结构。  相似文献   

11.
Multiwall carbon nanotubes (MWNT) were modified orderly with carboxyl groups and amino groups. The MWNT/gold nanoparticle composites were formed when the amino‐functionalized MWNT was interacted with gold colloids. The functionalized MWNT was characterized using Fourier transform infrared spectroscopy and X‐ray photoelectron spectroscopy. The amino‐functionalized MWNT allows further attaching gold nanoparticles through electrostatic interaction between the negatively charged gold nanoparticles and amino groups on the surface of the MWNT. The composite of gold nanoprticles and amino‐functionalized MWNT was characterized by transmission electron microscopy. This method decorating carbon nanotubes can be used to identify the location of functional groups, i.e. defect sites on carbon nanotubes.  相似文献   

12.
This study describes the preparation of polypyrrole (PPy)/multiwalled carbon nanotube (MWNT) composites by in situ chemical oxidative polymerization. Various ratios of MWNTs, which served as hard templates, were first dispersed in aqueous solutions with the surfactant cetyltrimethylammonium bromide to form micelle/MWNT templates and overcome the difficulty of MWNTs dispersing into insoluble solutions of pyrrole monomer, and PPy was then synthesized via in situ chemical oxidative polymerization on the surface of the templates. Raman spectroscopy, Fourier transform infrared (FTIR), field‐emission scanning electron microscopy (FESEM), and high‐resolution transmission electron microscopy (HRTEM) were used to characterize the structure and morphology of the fabricated composites. Structural analysis using FESEM and HRTEM showed that the PPy/MWNT composites were core (MWNT)–shell (PPy) tubular structures. Raman and FTIR spectra of the composites were almost identical to those of PPy, supporting the idea that MWNTs served as the core in the formation of a coaxial nanostructure for the composites. The conductivities of these PPy/MWNT composites were about 150% higher than those of PPy without MWNTs. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 1413–1418, 2006  相似文献   

13.
聚3-辛基噻吩/MWNTs复合材料的导电性能研究   总被引:2,自引:0,他引:2  
采用在氯仿溶液中超声共混, 制备聚3-辛基噻吩(P3OT)和多壁碳纳米管(MWNTs)复合材料. 当MWNTs掺杂量为3%时复合材料的电导率为1.43 S•m-1, 达到纯MWNTs的电导率水平. 用FTIR光谱, TG, UV-Vis光谱, XPS和FESEM进行研究分析, 认为MWNTs的离域电子与P3OT主链上的π电子之间形成π-π共轭, 增加了P3OT主链的有效共轭度, 被掺杂的P3OT具有很高的电导率, 提高了复合材料的导电性能. MWNTs与被掺杂的P3OT组成相对独立的导体单元, 对复合材料的导电网络形成起着主要作用.  相似文献   

14.
聚噻吩/多壁碳纳米管复合材料结构与导电机理的研究   总被引:3,自引:0,他引:3  
从结构和相互作用方面对聚噻吩(PTh)/多壁碳纳米管(MWNTs)复合材料进行了研究, 结果表明: 一方面聚噻吩本身的结构对其导电性能有一定的影响, 另一方面MWNTs作为一种掺杂剂, 和聚噻吩之间存在强的相互作用, 电子从MWNTs转移到聚噻吩. MWNTs和它周围被掺杂的聚噻吩通过π-π共轭作用形成相对独立的导电单元, 在复合材料的导电体系中起到主要作用, 随着这种导电单元数量的增加直至相互接触, 形成大的导电体系, 复合材料的电导率达到最大值.  相似文献   

15.
Amino modified multiwall carbon nanotubes (MWNTs) are prepared, respectively, by two ways: the conventional one‐step method that directly treats acyl chloride functionalized MWNTs with 4, 4′‐diaminodiphenyl ether (ODA), giving the amino modified MWNT (Di‐MWNT), as well as an improved two‐step method in which acyl chloride functionalized MWNT react with mono‐Boc protected ODA first and then the Boc‐groups are deprotected to provide the amino modified MWNT (NH2‐MWNT). Anhydride‐terminated polyimide (PI) composite films based on NH2‐MWNT and Di‐MWNT are fabricated by solution blending and consequent planar casting. The exposed amino groups of NH2‐MWNT create strong covalent bonds with the anhydride‐terminated polyamide acid in the course of N‐acylation and curing chemical reactions. Solubility examinations of nanotubes and morphologies of the composite films indicate that the dispersion of NH2‐MWNT is significantly better than Di‐MWNT in PI matrix and NH2‐MWNT can form connected network throughout the PI matrix which makes the NH2‐MWNT/PI film presenting superior conductivity. Both morphologies and mechanical properties of the composites show that NH2‐MWNT has stronger interfacial interaction with the PI matrix. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013 , 51, 3449–3457  相似文献   

16.
将磺化聚苯乙炔(SPPA)与多壁碳纳米管(MWNT)超声共混制备得到SPPA/MWNT复合材料. 用四探针电阻率测试、场发射扫描电镜(FESEM)、XPS、UV-Vis、XRD等方法对复合材料导电机理进行研究. 结果表明, SPPA/MWNT的电导率发生两次突跃;掺杂剂MWNT具有低的临界阈值; 临界阈值附近, 复合材料中MWNT具有不连续分布的现象及复合材料电阻呈负温度系数(NTC)效应; SPPA/MWNT复合材料中MWNT的碳原子对SPPA 进行掺杂. 推测复合材料的导电机理为, 共轭聚合物SPPA不仅被导电粒子MWNT物理填充, 同时还被MWNT的碳原子掺杂, 使复合材料中存在两种导电通路而导电, 一是因被掺杂而成为高电导率主体的SPPA相互接触形成的导电通路, 二是MWNT相互接触形成的导电通路.  相似文献   

17.
Summary: Electro‐active shape‐memory composites were synthesized using conducting polyurethane (PU) composites and multi‐walled carbon nanotubes (MWNTs). Surface modification of the MWNTs (by acid treatment) improved the mechanical properties of the composites. The modulus and stress at 100% elongation increased with increasing surface‐modified MWNT content, while elongation at break decreased. MWNT surface modification also resulted in a decrease in the electrical conductivity of the composites, however, as the surface modified MWNT content increased the conductivity increased (an order of 10−3 S · cm−1 was obtained in samples with 5 wt.‐% modified‐MWNT content). Electro‐active shape recovery was observed for the surface‐modified MWNT composites with an energy conversion efficiency of 10.4%. Hence, PU‐MWNT composites may prove promising candidates for use as smart actuators.

The electro‐active shape‐recovery behavior of PU‐MWNT composites. The pictured transition occurs within 10 s when a constant voltage of 40 V is applied.  相似文献   


18.
Differential scanning calorimetry (DSC), polarized optical microscopy, and X‐ray diffraction methods were used to investigate the isothermal crystallization behavior and crystalline structure of poly(?‐caprolactone) (PCL)/multiwalled carbon nanotube (MWNT) composites. PCL/MWNT composites were prepared via the mixing of a PCL polymer solution with carboxylic groups containing multiwalled carbon nanotubes (c‐MWNTs). Both Raman and Fourier transform infrared spectra indicated that carboxylic acid groups formed at both ends and on the sidewalls of the MWNTs. A transmission electron microscopy micrograph showed that c‐MWNTs were well separated and uniformly distributed in the PCL matrix. DSC isothermal results revealed that introducing c‐MWNTs into the PCL structure caused strongly heterogeneous nucleation induced by a change in the crystal growth process. The activation energy of PCL drastically decreased with the presence of 0.25 wt % c‐MWNT in PCL/c‐MWNT composites and then increased with increasing MWNT content. The result indicated that the addition of c‐MWNT to PCL induced heterogeneous nucleation (lower total activation energy) at a lower c‐MWNT content and then reduced the transportation ability of polymer chains during crystallization processes at a higher MWNT content (higher total activation energy). A correlation between the crystallization kinetics, melting behavior, and crystalline structure of PCL/c‐MWNT composites was also discussed. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 598–606, 2006  相似文献   

19.
We demonstrate here a feasible approach to the preparation of multiwalled carbon nanotube (MWNT)/polypyrrole (PPy) core–shell nanowires by in situ inverse microemulsion. Transmission electron microscopy and scanning electron microscopy showed that the carbon nanotubes were uniformly coated with a PPy layer with a thickness of several to several tens of nanometers, depending on the MWNT content. Fourier transform infrared spectra suggested that there was strong interaction between the π‐bonded surface of the carbon nanotubes and the conjugated structure of the PPy shell layer. The thermal stability and electrical conductivity of the MWNT/PPy composites were examined with thermogravimetric analysis and a conventional four‐probe method. In comparison with pure PPy, the decomposition temperature of the MWNT/PPy (1 wt % MWNT) composites increased from 305 to 335 °C, and the electrical conductivity of the MWNT/PPy (1 wt % MWNT) composites increased by 1 order of magnitude. The current–voltage curves of the MWNT/PPy nanocomposites followed Ohm's law, reflecting the metallic character of the MWNT/PPy nanocomposites. The cyclic voltammetry measurements revealed that PPy/MWNT composites showed an enhancement in the specific charge capacity with respect to that of pure PPy. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 6105–6115, 2005  相似文献   

20.
电纺丝是一种利用聚合物溶液或熔体在强电场中进行喷射纺丝的加工技术,所制得的纤维、直径一般在数十纳米至几微米之间,比传统方法制得的纤维直径小几个数量级,是获得纳米尺寸长纤维的有效方法之一.  相似文献   

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