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1.
以苯胺和过硫酸胺为原料,采用原位聚合方法合成了聚苯胺/碳化钨(PANI/WC)导电复合材料。研究了反应体系中碳化钨的含量对复合材料电导率的影响,确定了较佳的聚合条件,并且通过FT-IR、XRD、XPS和DSC-TGA等手段对复合材料的结构和性能进行了表征和分析。结果表明:碳化钨(WC)的加入提高了聚苯胺的电子导电性能,复合材料中聚苯胺组分为无定型,WC的晶型在反应前后并未发生变化,复合材料的热稳定性好并且质子化程度更高。  相似文献   

2.
A new nanocomposite of vanadium pentoxide (V2O5) and polyaniline (PANI) were synthesized by in situ oxidative polymerization/intercalation on V2O5 powder at room temperature. The reaction was facile and topotactic, forming polyaniline as the emeraldine salt. It was indicated that V2O5 itself can catalyze the oxidative polymerization of aniline and that layered structure could make aniline intercalate into the V2O5 framework. It makes the in situ polymerization feasible to occur in the layer of V2O5 structure. XRD results showed PANI/V2O5 nanocomposite possessed lamellar mesostructure, which was determined by an X-ray diffraction peak at 6.5° and SEM photograph. And FT-IR spectrum suggested that there was interaction between PANI and V2O5. The hybrid had better thermal stability in N2 and air ambience.  相似文献   

3.
Conductive polyaniline/tungsten carbide (PANI/TC) composite was synthesized via polymerization of the aniline monomer by (NH4)2S2O8/H2SO4 oxidant system in the presence of an aqueous suspension of TC. The structure, thermal stability and conductivity of PANI/TC composite were studied and the results were also compared with the pure PANI. The results showed that there was a strong interaction between the TC particles and PANI molecular chains. The crystalline structure of TC remained undisturbed upon with interaction with PANI chains. The thermal stability of PANI/TC composite was better than that of pure PANI. The direct current conductivity values of PANI/TC composite decreased slowly as the temperature increased from 25 to 165°C and PANI/TC composite exhibited significantly higher conductivity than the pure PANI.  相似文献   

4.
聚苯胺/纳米二氧化锰复合材料Ⅰ.原位氧化合成制备   总被引:6,自引:1,他引:6  
用固相合成法制备了纳米二氧化锰(nm-MnO2),并通过原位聚合法制备了聚苯胺/纳米二氧化锰复合材料。研究结果表明:在苯胺/nm-MnO2的盐酸反应体系中,nm-MnO2可以使苯胺氧化聚合。在一定的nm-MnO2用量下,聚苯胺的产率随苯胺添加量的增加而下降,nm-MnO2在产物中的含量也随之下降,且含量很低。在苯胺:/nm-MnO2/过硫酸铵的反应体系中,研究了Nm-MnO2通过两种不同的加料方式原位制备PA-NI/nm-MnO2复合材料的合成条件。第一种方式为nm-MnO2和过硫酸铵同时与苯胺混合,一起参与苯胺的氧化聚合。第二种方法是先将过硫酸铵和苯胺混合,3min后再将nm-MnO2加入反应体系中。研究表明:第一种加料方式得到的队NI/nm-MnO2中nm-MnO2的含量很低;第二种加料方式可以得到高nm-MnO2含量(w=0.14-0.73)的产物,其电导率约10^-4S/cm。  相似文献   

5.
Vertical polyaniline (PANI) nanowire arrays on graphene‐sheet‐coated polyester cloth (RGO/PETC) were fabricated by the in situ chemical polymerization of aniline. The 3D conductive network that was formed by the graphene sheets greatly enhanced the conductivity of PANI/RGO/PETC and improved its mechanical stability. PANI nanowire arrays increased the active surface area of PANI, whilst the hierarchically porous structure of the PANI/RGO/PETC electrode facilitated the diffusion of the electrolyte ions. Electrochemical measurements showed that the composite electrode exhibited a maximum specific capacitance of 1293 F g?1 at a current density of 1 A g?1. Capacitance retention was greater than 95 %, even after 3000 cycles, which indicated that the electrode material has excellent cycling stability. Moreover, the electrode structure endowed the PANI/RGO/PETC electrode with a stable electrochemical performance under mechanical bending and stretching.  相似文献   

6.
研究了原位聚合法制备聚酰胺/聚苯胺导电纤维,并对制备的复合纤维进行红外及光学显微镜测试,结果表明聚苯胺与纤维成功复合。对制备的复合纤维进行电导率测试,采用控制单一变量法探讨了苯胺单体在不同的条件下聚合对纤维电导率的影响,并讨论了反应温度对聚合过程和电导率的影响,得出最佳的工艺条件为:纤维经30%的甲酸溶液预处理20min,苯胺单体浓度为0.8M,氧化剂过硫酸铵浓度为1M,掺杂酸为盐酸,浓度为0.8M,冰水浴条件,反应时间为4h,得到的聚酰胺/聚苯胺导电纤维的电导率为3.7S/m。  相似文献   

7.
Graphene oxide (GO)–polyaniline (PANI) composite is synthesized by in situ polymerization of aniline in the presence of GO as oxidant, resulting in highly crystalline and conductive composite. Fourier transform infrared spectrum confirms aniline polymerization in the presence of GO without using conventional oxidants. Scanning electron microscopic images show the formation of PANI nanofibers attached to GO sheets. X‐ray diffraction (XRD) patterns indicate the presence of highly crystalline PANI. The sharp peaks in XRD pattern suggest GO sheets not only play an important role in the polymerization of aniline but also in inducing highly crystalline phase of PANI in the final composite. Electrical conductivity of doped GO–PANI composite is 582.73 S m?1, compared with 20.3 S m?1 for GO–PANI obtained by ammonium persulfate assisted polymerization. The higher conductivity appears to be the result of higher crystallinity and/or chemical grafting of PANI to GO, which creates common conjugated paths between GO and PANI. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 1545–1554  相似文献   

8.
Spiny polyaniline (PANI) spheres (urchin-like) were coated on a poly(tetrafluoroethylene) (PTFE) membrane via a counter-diffuse interfacial oxidation polymerization of aniline in an aqueous medium. The produced composite membrane has both unexpected superhydrophilicity and conductivity. The microstructure and morphology of the composite membrane were characterized by FTIR, UV-vis, XRD, TGA, and SEM. Effects of reagent concentrations and polymerization time on the membrane morphology and properties were studied systematically. A possible formation mechanism of the urchin-like polyaniline nanospheres on PTFE surface has been briefly discussed. The co-effect of both spherical micelles formed by Nafion and nanofibrous micelles formed by aniline/p-toluenesulfonic acid was considered to be a reason to produce the urchin-like PANI nanospheres. The PTFE/Nafion/PANI composite membrane showed a convertible hydrophilic/hydrophobic feature via adjusting acidity/alkalinity of an aqueous medium and also was able to adsorb heavy metal-ions from the medium.  相似文献   

9.
以苯胺为原料, 采用原位聚合法在聚四氟乙烯(PTFE)基体上合成聚苯胺/聚四氟乙烯(PANI/PTFE)复合膜. 利用光学显微镜、 扫描电子显微镜(SEM)、 傅里叶变换红外光谱(FTIR)、 紫外-可见吸收光谱(UV-Vis)和静态水接触角测试对PANI/PTFE复合膜的形貌、 结构和浸润性进行分析, 并对其油包水乳液分离性能、 通量和循环使用性能进行了测试. 研究结果表明, PANI/PTFE复合膜仅在重力条件就能有效分离油包水乳液; 而且重复数十次过滤后, PANI/PTFE复合膜仍具有良好的抗污能力和分离性能.  相似文献   

10.
Polymerization of aniline on polyaniline membranes   总被引:1,自引:0,他引:1  
When solutions of aniline hydrochloride and ammonium peroxydisulfate were separated by a semipermeable cellulose membrane, the reactants met at the membrane and produced a polyaniline (PANI) membrane at the interface. The oxidative polymerization of aniline then proceeded in situ on the PANI-cellulose composite membrane. PANI was produced entirely at the monomer side of the membrane; about 80% conversion of aniline to PANI was observed after 24 h. The oxidation of aniline with peroxydisulfate consists in the transfer of electrons from aniline to the oxidant; it is proposed that electrons pass through the PANI membrane, which is conducting, and electroneutrality is maintained by the simultaneous transfer of protons. The reaction between aniline and peroxydisulfate thus takes place without the need for both reactant molecules to be in physical contact. The residual aniline is located only at its original side of the membrane, but the product of ammonium peroxydisulfate conversion, ammonium hydrogen sulfate, was found on both sides of the membrane. Fourier-transform infrared spectroscopy has been used to analyze PANI, the reaction residues and byproducts, and to prove that PANI is protonated with counter-ions of the sulfate type. Using this technique, we have detected only small differences in the molecular structure of PANI prepared with the membrane-separated reactants and in the polymerization when reactants were mixed; also, the molecular weights differed only marginally. The conductivity of both types of PANI was about the same. The repeated polymerization of aniline on the earlier prepared PANI-cellulose membrane yielded similar results, thus confirming the proposed concept of coupled electron- and proton-transfer through the PANI membrane.  相似文献   

11.
采用1-羧甲基-3-甲基咪唑氯化盐离子液体对钠化蒙脱土进行插层改性,然后用苯胺的盐酸溶液进行二次插层,以过硫酸铵为氧化剂,盐酸溶液为掺杂剂,使进入离子液体/蒙脱土(CMMIm/MMT)层间的苯胺(An)发生氧化聚合反应,制备了一种具有良好导电性的聚苯胺/离子液体/蒙脱土复合材料(PANI/CMMIm/MMT).用红外光谱、X-射线衍射,热重分析和DSC对样品进行了表征.结果表明当离子液体/蒙脱土用量为7.5%、盐酸浓度为1mol/L、过硫酸铵与苯胺的摩尔比为1∶1、0℃下反应6h时制备的PANI/CMMIm/MMT纳米复合材料电导率最高,达到了0.3S/cm,是相同条件下聚苯胺/钠化蒙脱土纳米复合材料电导率的2.5倍,聚苯胺的7.5倍.  相似文献   

12.
层层自组装原位聚合聚苯胺复合膜成膜机理研究   总被引:2,自引:0,他引:2  
从苯胺单体出发, 通过原位聚合、现场掺杂以及基于静电力的层层自组装制备了聚苯胺复合膜. 通过苯胺活性溶液的温度及颜色变化跟踪聚合反应进程, 同时考察不同聚合反应阶段所得聚苯胺复合膜的紫外-可见吸收, 并进一步探讨聚苯胺复合膜的成膜机理. 研究表明, 成膜机制是由聚合反应初始阶段的苯胺阳离子或苯胺阳离子自由基通过静电作用快速吸附到负电性的基片表面, 形成均匀的聚合中心, 链增长生成聚苯胺; 该聚苯胺在酸性条件下经现场掺杂显电正性, 可吸附电负性的聚苯乙烯磺酸钠(PSS), 以此循环层层组装得到多层聚苯胺复合膜.  相似文献   

13.
A preparation method for a new electrode material based on the LiNi0.8Co0.2O2/polyaniline (PANI) composite is reported. This material is prepared by in situ polymerization of aniline in the presence of LiNi0.8Co0.2O2 assisted by ultrasonic irradiation. The materials are characterized by XRD, TG-DTA, FTIR, XPS, SEM-EDX, AFM, nitrogen adsorption (BET surface area) and electrical conductivity measurements. PANI in the emeraldine salt form interacts with metal-oxide particles to assure good connectivity. The dc electrical conductivity measurements at room temperature indicate that conductivity values are one order of magnitude higher in the composite than in the oxide alone. This behavior determines better reversibility for Li-insertion in charge-discharge cycles compared to the pristine mixed oxide when used as electrode of lithium batteries.  相似文献   

14.
采用乳液法, 以过硫酸铵(APS)和次氯酸钠(NaClO)为复合氧化剂合成导电聚苯胺(PANI). 考察了NaClO 的加入与否对PANI 微观形貌与电化学性能(循环伏安和电导率)的影响, 以及APS、乳化剂十二烷基苯磺酸钠(SDBS)和NaClO的用量对PANI 电化学性能的影响. 结果表明: NaClO 的加入对PANI 的微观取向结构具有重要的影响. 与采用单一APS 合成的PANI 相比, 复合氧化剂合成的PANI 具有较高的循环伏安峰电流以及更加优异的电导率(约为前者的2.6倍). 当苯胺(An)与APS 的物质的量比(nAn:nAPS )为8:7, An 与SDBS 的物质的量比(nAn:nSDBS )为10:4, NaClO 用量为5%(质量分数)时, PANI 的各项性能指标达到最好; 紫外可见光谱和红外光谱的表征结果表明, 采用复合氧化剂并未对PANI 的分子结构产生明显的影响.  相似文献   

15.
New types of conducting composites using red mud as an inorganic substrate and polyaniline as the conducting phase were prepared. Red mud/polyaniline (RM/PANI) composites were synthesized in acidic aqueous solution by the chemical oxidative polymerization of aniline using ammonium peroxydisulfate as the oxidant. The composites exhibit conductivities in the 0.42-5.2 S cm−1 range, depending on the amount of polyaniline. They were characterized by infrared and UV-vis spectroscopy, scanning electron microscopy and X-ray diffraction. The IR and X-ray results show that PANI is deposited on the RM surface. The composites have a globular structure and the PANI globules synthesized on the surface of RM are smaller than those prepared under the same conditions without the substrate. Thermogravimetric analysis was used for investigation of the thermal stability of the composites. The thermal stability of the conductivity of RM/PANI composites was studied by ageing at 125 °C, the conductivity being measured in situ during this process.  相似文献   

16.
A composite material of a silica-based mesoporous molecular sieve, MCM-41, with conducting polyaniline (PANI) inside the uniformly aligned one-dimensional channels (PANI/MCM-41) was prepared and its nanocomposite formation was confirmed through an electrical conductivity measurement. This nanocomposite particle was adopted for a dispersed phase in electrorheological (ER) fluids, and the ER property was measured using a Couette-type rotational rheometer equipped with a high voltage generator. Suspension of PANI/MCM-41 showed ER properties more enhanced than those of MCM-41 or PANI alone as a result of the anisotropic polarization of the PANI/MCM-41 nanocomposite.  相似文献   

17.
Poly(styrene sulfonic acid) membranes (Neosepta CMX, Tokuyama Corp.) have been modified by in situ polymerization of aniline. (NH4)2S2O8, FeCl3, H2O2, and KIO3 were used as oxidizing agents, and two different modification methods (single-step versus two-step) were studied. The composite membranes were characterized by scanning electron microscopy, X-ray photoelectron spectroscopy, elemental analysis, electrodialysis, ion-exchange capacity, and conductivity measurements. Our results demonstrate that it is possible to control the polymerization site of aniline which in turn affects the membrane selectivity properties. Hence, composite membranes having a very thin and homogeneous surface polyaniline layer lead to a very low transport of Zn 2+ without increasing significantly the resistance to H+ conductivity. On the other hand, membranes containing about the same quantity of PANI but inside the membrane do not block the transport of Zn 2+.  相似文献   

18.
In this study, polyamide6 (PA6) nanofiber mats were fabricated through the electrospinning process. The nanofibers were coated by polyaniline (PANI) using the in situ polymerization of aniline in the presence of graphene oxide. The composite of the PANI/graphene oxide–coated nanofiber mat was treated with hydrazine monohydrate to reduce graphene oxide to graphene, and this was followed by the reoxidation of PANI. Field emission scanning electron microscopy (FESEM), Fourier transform infrared spectroscopy (FTIR), wide angle X‐ray diffraction (WAXD), thermal gravimetric analysis (TGA), tensile strength tests, electrical conductivity measurements, cyclic voltammetry (CV), and charge/discharge measurements were conducted on the composite PA6/graphene nanofiber mats. It was found that the surface of the PA6 nanofibers was coated uniformly with the granular PANI and graphene oxide. Besides, the composite nanofibers showed good tensile and thermal properties. Their electrical conductivity and specific capacitance, when used as a separator in the cell, were 1.02 × 10?4 S/cm and 423.28 F/g, respectively. Therefore, the composite PANI/reduced graphene oxide–coated PA6 nanofiber mats could be regarded as suitable candidates for application in energy storage devices.  相似文献   

19.
To reduce the charge‐transfer resistance of supercapacitors and achieve faster reversible redox reactions, ternary Ni‐Co‐Fe layered double hydroxide was prepared by using the urea method and then calcined to give NiCoFe oxide (NiCoFeO). To enhance conductivity, a polyaniline (PANI) conductive layer was assembled on the surface of the NiCoFeO particles by in situ oxidative polymerization of aniline monomers. The as‐prepared NiCoFeO/PANI composite was successful employed as a supercapacitor electrode. It was found that the NiCoFeO/PANI composite displayed good cycling stability, with a capacity loss of only 29.54 % after 5000 cycles. Furthermore, the NiCoFeO/PANI composite also exhibited excellent supercapacitor performance, with a high specific capacity of 843 F g?1 at a current density of 2 A g?1, whereas NiCoFeO showed a specific capacity of only 478 F g?1. This result was attributed to the synergistic effect between NiCoFeO and PANI. The facile synthesis strategy and excellent electrochemical performance suggest that NiCoFeO/PANI is a promising economical electrode material for applications in supercapacitors.  相似文献   

20.
Chemically modified ordered mesoporous carbon CMK-3 materials were prepared by means of an easy wet-oxidative method in 2 mol/L nitric acid aqueous solution. A large amount of oxygen-containing functional groups were introduced onto the CMK-3 surface. Modified CMK-3(m-CMK-3) and aniline monomer were polymerized via an in situ chemical oxidative polymerization method. Morphological characterizations of m-CMK-3/PANI (polyaniline) composites were carried out via field emission scanning electron microscopy(SEM)...  相似文献   

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