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1.
《应用化工》2022,(1):118-121
3,5-二叔丁基苯酚通过溴化、磷酸化和锂-溴交换及阴离子phospha-Fries重排反应,合成了4,6-二叔丁基-2-羟基苯膦酸二乙酯,在碱性条件下,与酰氯化的多壁碳纳米管反应,制备苯基膦酸酯共价修饰的多壁碳纳米管(MWCNTs-COPPN)。核磁共振波谱、红外光谱和热重分析了产物的组成结构,并且对比了碳纳米管修饰前后的分散性。结果表明,苯基膦酸酯成功地对碳纳米管表面进行了有机修饰,有助于提高其在有机溶剂中的分散性。  相似文献   

2.
3,5-二叔丁基苯酚通过溴化、磷酸化和锂-溴交换及阴离子phospha-Fries重排反应,合成了4,6-二叔丁基-2-羟基苯膦酸二乙酯,在碱性条件下,与酰氯化的多壁碳纳米管反应,制备苯基膦酸酯共价修饰的多壁碳纳米管(MWCNTs-COPPN)。核磁共振波谱、红外光谱和热重分析了产物的组成结构,并且对比了碳纳米管修饰前后的分散性。结果表明,苯基膦酸酯成功地对碳纳米管表面进行了有机修饰,有助于提高其在有机溶剂中的分散性。  相似文献   

3.
为了增加多壁碳纳米管(MWCNTs)表面活性,通过浓H2SO4和浓HNO3处理过的MWCNTs与SOCl2回流进而与合成的N-乙基-3,6-二氨基咔唑反应,得到了有机修饰的MWCNTs.用傅立叶变换红外(FTIR)光谱对有机修饰的MWCNTs结构进行研究.研究结果结构表明:有机修饰的MWCNTs红外光谱在1617和16...  相似文献   

4.
以多壁碳纳米管(MWCNT)和聚乙烯(PE)为原料,采用溶液拉伸法制备了一种新型复合材料薄膜PE/MWCNT。研究了拉膜温度、转筒转速和对二甲苯溶液浓度等因素对PE/MWCNT成膜性能的影响,获得了最佳的成膜条件。通过扫描电镜、差示扫描量热仪、热重分析仪与微机控制万能试验机对其结构和性能进行表征。PE/MWCNT超薄膜填补了复合材料的空白。  相似文献   

5.
综述了碳纳米管非共价功能化的一些新的研究进展情况,介绍了碳纳米管非共价功化的种类、方法和意义,并对功能化后的碳纳米管的性能表征方法及应用前景进行了介绍。针对碳纳米管非共价功能化后虽可同时保持原有的物化性质和引入的物化性质,但表征非常困难这一矛盾进行了评述,并对今后的发展进行了展望。  相似文献   

6.
7.
多壁碳纳米管/高密度聚乙烯复合材料的导电行为研究   总被引:1,自引:0,他引:1  
采用超声波分散溶液混合法,制备出导电性能优良的多壁碳纳米管(MWNTs)/高密度聚乙烯(HDPE)导电复合材料。研究了不同含量及长径比的MWNTs对HDPE导电性能的影响。结果表明:MWNTs可以显著提高复合材料的导电性,其体积电阻率由1017Ω.m降至107Ω.m;长径比较小的MWNTs分散性较好,并能显著提高材料的PTC(正温度系数效应)强度,当w(MWNTs-60100)=7%(相对于材料总质量而言)时,材料的PTC强度达到2.8。采用差示扫描量热(DSC)法分析了复合材料的结晶行为,证明MWNTs可以成为HDPE的成核剂,并能提高HDPE的成核速率,使晶粒尺寸分布变窄。  相似文献   

8.
通过原位氧化聚合法制备出多壁碳纳米管/聚苯胺(MWCNTs/PANI)纳米复合材料,并利用傅里叶红外光谱(FTIR)、X射线衍射(XRD)、扫描电子显微镜(SEM)和透射电镜(TEM)等手段对其进行表面化学组成和微观形貌进行表征。结果表明MWCNTs/PANI纳米复合物被成功制备。  相似文献   

9.
采用溶剂热法制备磁性多壁碳纳米管(MWCNTs@Fe3O4),用聚乙烯亚胺(PEI)进行表面修饰,得到MWCNTs@Fe3O4/PEI。对吸附剂进行表征,研究p H、离子强度和天然有机物对水中铬(Ⅵ)的吸附及吸附剂的循环再生能力。结果表明,最佳吸附p H=3,吸附过程符合准二级动力学模型和Langmuir等温吸附模型,离子强度抑制Cr(Ⅵ)的吸附;腐殖酸对Cr(Ⅵ)的吸附影响不大。在6次吸附解吸后,吸附剂仍有良好的吸附性能。  相似文献   

10.
首先将多壁碳纳米管(MWNTs)通过混酸氧化处理,得到氧化多壁碳纳米管(MWNTs-COOH),再将其与乙二胺(EDA)在N,N'-二环己基碳二亚胺(DCC)与4-二甲氨基吡啶(DMAP)的复合催化体系下反应,制得氨化多壁碳纳米管(MWNTs-NH2),并通过场发射扫描电镜观察、傅里叶红外光谱分析、热失重分析、X射线衍射分析、拉曼光谱分析等测试方法对制得的MWNTs-NH2进行结构性能表征。结果表明:通过氧化处理后,MWNTs上引入了羧基,且其长度变短,同时处理后其结构受到一定程度的破坏;通过氨化处理后,MWNTs上引入了酰胺键,MWNTs上乙二胺的接枝率为7.46%,氨化处理过程并未破坏MWNTs-COOH的结构。  相似文献   

11.
采用原子转移自由基聚合的方法将聚乙二醇(PEG)接枝到多壁碳纳米管(MWNTs)上,然后利用平板硫化机制备出聚甲醛(POM)/MWNTs-PEG复合材料。利用扫描电子显微镜、透射电子显微镜、红外光谱和热重分析对MWNTs-PEG进行表征。通过差式扫描量热仪研究了该复合材料结晶行为的变化,用Jeziorny法和Mo法对其进行非等温结晶动力学分析。结果表明,PEG均匀接枝到MWNTs上;MWNTs-PEG的加入具有异相成核的作用,使POM结晶温度向高温区移动,结晶速率提高,半结晶时间缩短;结晶速率常数值增加,F(T)值降低;有效结晶活化能降低;MWNTs-PEG最终起到促进POM结晶的作用。  相似文献   

12.
由碳纳米管的功能化有共价键和非共价键两种方法。共价键功能化的机理是通过氧化或还原反应在碳纳米管表面生成极性或反应性基团(表面基团化),继而通过化学反应使碳纳米管表面有机化或聚合物化。非共价键功能化的机理是基于碳纳米管表面的?体系和疏水性可与含?电子的芳烯化合物发生?-?相互作用或与含疏水链的表面活性剂发生物理吸附。本文综述碳纳米管功能化的研究进展,完善了Kim等提出的碳纳米管功能化表面的代数表示:表面基团化的为1G,表面有机化的为2G,表面聚合物化的为3G。  相似文献   

13.
In this work, synthesis and optical properties of a new composite based on poly(o-phenylenediamine) (POPD) fiber like structures, poly(vinylidene fluoride) (PVDF) spheres and double-walled carbon nanotubes (DWNTs) are reported. As increasing the PVDF weight in the mixture of the chemical polymerization reaction of o-phenylenediamine, the presence of the PVDF spheres onto the POPD fibers surface is highlighted by scanning electron microscopy (SEM). The down-shift of the Raman line from 1421 cm−1 to 1415 cm−1 proves the covalent functionalization of DWNTs with the POPD-PVDF blends. The changes in the absorbance of the IR bands peaked around 840, 881, 1240 and 1402 cm−1 indicate hindrance steric effects induced of DWNTs to the POPD fiber like structures and the PVDF spheres, as a consequence of the functionalization process of carbon nanotubes with macromolecular compounds. The presence of the PVDF spheres onto the POPD fiber like structures surface induces a POPD photoluminescence (PL) quenching process. An additional PL quenching process of the POPD-PVDF blends is reported to be induced in the presence of DWNTs. The studies of anisotropic PL highlight a change of the angle of the binding of the PVDF spheres onto the POPD fiber like structures surface from 50.2° to 38° when the carbon nanotubes concentration increases in the POPD-PVDF/DWNTs composites mass up to 2 wt.%.  相似文献   

14.
采用自制的硅烷类改性剂(s-PEG)对经过酸氧化的多壁碳纳米管(MWNTs)进行表面改性处理,并通过共混法制备了MWNTs/水性聚氨酯(WPU)复合材料,研究了MWNTs的添加对复合材料性能的影响.结果表明,改性剂s-PEG成功地包覆于MWNTs表面,形成了s-PEG壳层,包覆率约为25%.改性MWNTs (s-PEG-MWNTs)的添加可以明显改善WPU复合材料的拉伸性能,当s-PEG-MWNTs的添加量为1%时,复合材料的拉伸强度和断裂伸长率比未添加MWNTs的材料分别提高了597%和152%.s-PEG-MWNTs在WPU基体中达到了良好的分散效果.此外,s-PEG-MWNTs的添加显著地增强了复合材料的导电性能.  相似文献   

15.
采用原位复合方法,合成了不同多壁碳纳米管(MWNTs)含量的PET纳米复合物。实验中采用超声波辅助(方法A)和球磨辅助(方法B)两种分散方法?用扫描电子显微镜(SEM)、差示扫描量热分析fDSC)、Instron拉伸实验等手段对MWNTs及其在PET基质中的形态、复合物的熔融和结晶行为以及物理机械性能进行了袁征。结果表明:MWNTs能够均匀分散于PET中,且长径比较小的MWNTs的分散程度更好一些。聚合物熔体结晶过程中,MWNTs具有明显的成核作用,最大可使熔融结晶温度提高24.1℃。与纯PET材料相比,含0.4%MWNTs的PET复合材料(A—PET-4)的拉伸强度和杨氏模量分别提高约17%和25%,断裂仲长率则大幅度降低。  相似文献   

16.
利用非共价修饰的方法,先在碳纳米管表面包裹上表面活性剂十六烷基三甲基溴化铵(CTAB)和聚丙烯酸钠(PAA),然后原位修饰上铜和银纳米粒子,制备出MWCNT/CTAB/PAA/M(M:Cu或Ag)纳米复合材料,最后通过XRD、SEM和TEM等技术对其进行表征。结果表明,利用这种简单的层层自组装方法能够在碳管上均匀地修饰金属纳米粒子,并且这两种金属纳米粒子的尺寸都小于5 nm。  相似文献   

17.
Poly(ethylene terephthalate) (PET) hybrids with newly synthesized functionalized multiwalled carbon nanotubes (MWNTs) were obtained by carrying out the in situ polycondensation of ethylene glycol with dimethyl terephthalic acid. The PET hybrids were melt-spun to produce monofilaments with various functionalized MWNT contents and draw ratios (DRs). The thermomechanical properties and morphologies of the PET hybrid fibers were determined using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), wide angle X-ray diffraction (XRD), electron microscopy (SEM and TEM), and a universal tensile machine (UTM). The XRD analysis and TEM micrographs show that the levels of nanosize dispersion can be controlled by varying the MWNT content. It was found that the addition of only a small amount of functionalized MWNTs was sufficient to improve the properties of the PET hybrid fibers. The maximum enhancement in the ultimate tensile strength was found to arise at a functionalized MWNT content of 0.5 wt %. However, the initial modulus was found to increase linearly with increases in the functionalized MWNT loading from 0 to 1.5 wt %. The thermal properties and conductivities of the PET hybrid fibers were found to be better than those of pure PET fibers. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

18.
An in situ lubrication dispersion method is developed to achieve electrical conductivity in PP containing a small amount of MWCNTs. Good dispersion of the MWCNTs in PP is observed even after a short mixing time because the interactions between the entangled nanotubes are reduced. By in situ lubrication dispersion, the electrical percolation threshold of the PP nanocomposite can be as low as 0.5–0.7 wt% MWCNT. Rheological data also support percolation at 0.5 wt% MWCNT. With 0.5 wt% MWCNT, the slope of G′ at low frequency approaches unity and shows non‐terminal behavior. The proposed dispersion method enhances the wetting of MWCNTs and improves MWCNT dispersion compared to both direct mixing of MWCNT powder with a polymer melt and conventional master batch dilution.

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19.
《分离科学与技术》2012,47(9):1344-1352
In this study, 3-mercaptopropyltriethoxysilane (MPTS) modified mesoporous silica based on multiwalled carbon nanotubes (MWCNTs@mSiO2-MPTS) was successfully prepared. The adsorption material was characterized and used for adsorbing Hg(II) ions from aqueous solution. The equilibrium data conformed better to the Langmuir isotherm with maximum adsorption capacity calculated 349.65 mg/g at 40ºC. The kinetics analysis revealed the adsorption process fitted well with the pseudo-second-order kinetic model. The thermodynamic parameters indicated the adsorption process was spontaneous and endothermic. All results obtained suggested that MWCNTs@mSiO2-MPTS may be employed as an efficient material for the adsorption or preconcentration of Hg(II) ions from aqueous solution.  相似文献   

20.
Multiwalled carbon nanotubes (MWNTs)‐reinforced poly(hydroxyaminoether) (PHAE) was fabricated via one pot graft‐from method. The modification of MWNTs and in situ polymerization of PHAE were combined in one reaction pot without interruption for the purification of modified carbon nanotubes. Fourier transform infrared, scanning electron microscopy, transmission electron microscopy, and Raman spectra clearly indicated that PHAE was successfully attached to the surface of MWNTs via esterification reaction between epoxy and carboxylic acid from MWNTs. Tensile tests showed that the tensile strength and modulus of PHAE/MWNTs composites were improved compared with that of pristine PHAE. Moreover, the reinforcing effect of one pot graft‐from method was found to be better than that of graft‐to method. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

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