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1.
刘淑玲  任静 《应用化工》2019,(1):104-108
分别采用物理球磨混合法、化学原位聚合法和化学原位聚合-还原法制备了聚吡咯/氧化石墨烯混合物、聚吡咯/氧化石墨烯(PPy/GO)和聚吡咯/还原氧化石墨烯(PPy/RGO)复合材料。通过三电极测试其电化学性能(循环伏安、恒流充放电和交流阻抗)。结果表明,通过化学原位聚合法制备的PPy/GO(304. 5 F/g)比电容远高于物理混合(16 F/g)和聚吡咯/还原氧化石墨烯(126. 4 F/g)。化学法原位聚合法制备PPy/GO最佳条件是冰浴条件下和加入表面活性剂对羟基苯磺酸钠。并通过X射线衍射(XRD)和扫描电子显微镜(SEM)对化学原位制备的PPy/GO组成、结构和形貌进行了表征。  相似文献   

2.
以三氯化铁为氧化剂,对甲苯磺酸为掺杂剂,采用化学氧化聚合法制得均聚物聚吡咯(PPy)、聚N-甲基吡咯(PNMPy)和共聚物聚吡咯–聚N-甲基吡咯(PPy–PNMPy)。通过扫描电镜、X射线衍射仪、紫外可见分光光度计、傅里叶变换红外光谱仪表征了3种聚合物的微观结构。采用电化学方法和腐蚀溶液浸泡法对比研究了裸钢片、PU(聚氨酯)涂层以及PU–PPy、PU–PNMPy和PU–PPy–PNMPy复合涂层的防腐性能。结果表明,共聚物PPy–PNMPy的致密性优于均聚物PPy和PNMPy。PU–PPy–PNMPy复合涂层的防腐性能和力学性能最优。  相似文献   

3.
利用超声波的分散、粉碎、活化、引发等多重作用以及吡咯单体与石墨烯的π-π相互作用,在实现石墨烯均匀分散的同时,使吡咯单体在石墨烯表面进行原位聚合反应,制备出聚吡咯/石墨烯(PPy/RGO)纳米复合材料。运用扫描电子显微镜(SEM)、红外光谱(FTIR)、X射线光电子能谱(XPS)等测试手段对PPy/RGO纳米复合材料的表面特性、化学组成及结构等进行了表征。在此基础上,研究了制备过程中的各种因素(如氧化剂、反应温度、石墨烯含量等)对PPy/RGO纳米复合材料产率及导电性能的影响。并采用热重分析(TGA)和导电测试分析了石墨烯含量对其热稳定性及电导率的影响。  相似文献   

4.
在纳米ZnO粒子存在的情况下,以吡咯单体为原料,对甲苯磺酸为掺杂剂,三氯化铁为氧化剂,采用化学氧化法制备了聚吡咯(PPy)/纳米ZnO复合物。采用扫描电子显微镜、紫外可见分光光度计和傅立叶变换红外光谱仪对复合物进行形貌观察和结构表征。分别以PPy和PPy/纳米ZnO复合物为填料,加入到聚氨酯(PUR)涂层中,再涂覆于碳钢片表面,之后浸泡在3.5%Na Cl溶液中,通过开路电位、极化曲线和交流阻抗研究涂层的防腐性能。结果表明,含有PPy/纳米ZnO复合物的PUR涂层耐腐蚀效果优于PUR/PPy涂层。  相似文献   

5.
为提高聚吡咯电极材料电化学性能,研制出一种普鲁士蓝(PB)镶嵌聚吡咯(PPy)薄膜电化学电容器电极。采用化学沉淀法结合气相聚合(VPP)法将同步合成的PB引入PPy薄膜中,制备了自支撑聚吡咯/普鲁士蓝(PPy/PB)复合电极材料。利用扫描电子显微镜、拉曼光谱、X射线粉末衍射技术等对复合材料的形貌及结构进行表征。在三电极体系和对称超级电容器中研究PPy/PB复合材料的电化学表现,研究结果表明,PPy/PB复合材料组装的超级电容器比电容高达447.6 F/g。不同电流密度下充放电性能研究表明,电流密度从1.0 A/g增大到10.0 A/g时,PPy/PB比容量保持率为70.8%,具有优异的倍率性能。通过4 000次恒流充放电后PPy/PB电容保持率为76.9%,高于纯PPy电极材料,显示出较好的电容性能。  相似文献   

6.
以BaTiO_3作为光催化剂,将其负载到石墨烯片(GR)上形成复合结构,通过气相沉积将聚吡咯(PPy)负载到GR/BaTiO_3结构上形成PPy包覆的PPy/GR/BaTiO_3光催化剂。分析PPy/GR/BaTiO_3光催化剂的形貌,并对其光催化性能进行表征。研究结果表明:由于GR和PPy之间的强共轭效应,可以极大地增加材料的比表面积。同时,GR作为电子接收体,可改善材料中光生载流子的快速复合,因此,相比于PPy和GR材料的光催化降解性能,PPy/GR/BaTiO_3光催化剂降解性能得到明显提高。  相似文献   

7.
以吡咯单体为原料,三氯化铁为氧化剂,加入纳米二氧化铈(CeO2)粒子通过化学氧化法制备了聚吡咯(PPy)/纳米CeO2复合材料。利用扫描电子显微镜、X射线衍射仪、紫外-可见分光光度计、傅里叶变换红外光谱仪对其进行了结构表征。并将涂覆分别含聚氨酯(PU)涂层、PPy/PU复合涂层、PPy/CeO2/PU复合涂层的碳钢片,浸泡在质量分数3.5%的Na Cl溶液中,通过开路电位和极化曲线研究耐腐蚀性能。结果表明,含有PPy/CeO2/PU复合涂层的防腐效果最佳,其腐蚀电位最大,腐蚀电流密度最小,腐蚀速率最小。  相似文献   

8.
采用化学氧化法制备聚吡咯(PPy),研究了氧化剂种类[FeCl3和(NH4)2S2O8]、反应温度(冰浴和室温)以及反应时间(6 h和12 h)对合成导电聚吡咯的影响,并对反应条件进行了优化。重点考察了不同浓度表面活性剂SDS掺杂对吡咯单体聚合的结构及形貌的影响,利用SEM、FT-IR、XRD、XPS、TGA、N2吸附-脱附等表征方法及电导率测试对产物进行分析。结果表明,合成导电聚吡咯的最佳工艺条件为:以FeCl3作氧化剂,在冰浴条件下反应6 h,产物电导率可达到0.076 9 S/cm;适量掺杂剂SDS的添加改变了样品的微观形貌,有利于提高PPy的热稳定性及导电性。  相似文献   

9.
采用两步法成功制备Sb-Sn O2/蒙脱石/聚吡咯(SSM/PPy)三元复合材料。首先制备出包覆均匀分散的SbSn O2/蒙脱石(SSM)二元复合物,然后再以二元复合物为载体,通过吡咯(Py)单体的化学氧化聚合获得最终产物。利用XRD、TEM、SEM、EDS、TG-DTA和BET对复合材料的结构和形貌等物理性质进行表征,通过循环伏安测试、恒电流充放电测试和交流阻抗测试对复合材料的电化学性能进行研究。结果表明,当吡咯的包覆量为20%时,所制备的三元复合材料的体积电阻率可达2.7Ω·cm、最大比电容为83.1 F/g,其电容性能的增强源于Sb-Sn O2、MMT与PPy三者的相互协同作用。  相似文献   

10.
采用化学氧化聚合法分别制备了盐酸、硫酸、硝酸及磷酸掺杂的聚吡咯(HCl-PPy、H_2SO_4-PPy、HNO_3-PPy和H_3PO_4-PPy)。用扫描电镜、傅里叶变换红外光谱仪和X射线衍射仪表征了掺杂聚吡咯的形貌和结构。将掺杂态聚吡咯与E44环氧树脂混合均匀,刷涂在Q235钢表面制得PPy/EP复合涂层,并通过电化学阻抗谱和加速浸泡试验考察了它们在3.5%NaCl溶液中的耐蚀性。4种无机酸掺杂聚吡咯都呈圆球颗粒状,部分有团聚现象。添加PPy明显提高了环氧涂层对碳钢的防腐作用,其中H_3PO_4-PPy的效果最好。  相似文献   

11.
Aiming to detect ammonia vapor, polypyrrole (PPy) thin layers were in situ coated on AT-cut 10 MHz quartz crystal microbalance QCM electrode by a facile chemical polymerization process using two organic acids as dopants, i.e. dodecylbenzene sulfonic acid (BDSA) and 1–5 naphthalene disulfonic acid (NDSA). Then after, polymers structural and morphological features were determined by FTIR, Raman spectroscopy and Scanning Electron Microscopy (SEM) techniques. Ammonia vapor sensing tests were related to QCM frequency changes recorded upon vapor adsorption and desorption on PPy films, it was found that frequency shifts varied linearly with both vapor concentration expressed in part per million (ppm) and polymer’s thin layer thickness given in nanometer (nm). This fact has been assumed to be mainly related to the electrostatic interactions established between ammonia vapor molecules and the polymer dopant agents. Tests have shown that films based PPy/NDSA exhibit high sensitivity around 3 ppm and detection limit of 4 ppm over films based PPy/DBSA. Interestingly, an excellent recovery time less than 3 min has been also recorded with PPy/NDSA thin layers. Moreover, when applying Fick’s second law, they have also shown a high diffusion constant.  相似文献   

12.
采用铬酸刻蚀和化学气相沉积聚吡咯处理了超高相对分子质量聚乙烯(UHMWPE)纤维。用DSC、DMA、X-射线衍射及SEM分析了纤维的热力学性能、结晶情况及纤维的表观形貌。结果表明,铬酸处理及化学气相沉积聚吡咯处理后,纤维的耐热性均有所提高,纤维表面变得更加粗糙,其中化学气相沉积聚吡咯处理的纤维变化更明显。  相似文献   

13.
Structural characteristics of polypyrrole (PPy)‐coated polycaprolactam (PA6) fiber composites prepared by chemical vapor deposition, in the presence of ferric chloride as the oxidizing agent, were investigated. A multi‐layered coating structure was observed by transmission electron microscopy (TEM), where a compact and denser layer existed between the PPy and PA6 fibers with two diffused layers on each side of the denser layer. The compact layer had a thickness of 200–300 nm. The experimental results show that there was no chemical interaction between PPy and PA6 in the PPy‐coated PA6 fibers. However, there was a stronger interaction between PPy and PA6 molecules in the interphase of PPy‐coated PA6 fiber after heat treatment at elevated temperature. The surface morphology of PPy‐coated PA6 fibers changed with the application of different processing treatments, e.g. swelling and heat treatment. Copyright © 2005 Society of Chemical Industry  相似文献   

14.
The carbon nanotubes (CNTs) have been loaded on the melamine foam (MF) to form the composite (CNTs/MF) by dip‐dry process, then polypyrrole (PPy) is coated on CNTs/MF (PPy/CNTs/MF) through chemical oxidation polymerization by using FeCl3·6H2O adsorbed on CNTs/MF as oxidant to polymerize the pyrrole vapor. Finally, CNTs are coated on the surface of PPy/CNTs/MF to increase the conductivity of the composite (CNTs/PPy/CNTs/MF) by dip‐dry process again. The composites have been characterized by X‐ray diffraction spectroscopy, scanning electron microscopy and electrochemical method. The results show that the structure of the composites has obvious influence on their capacitive properties. According to the galvanostatic charge/discharge test, the specific capacitance of CNTs/PPy/CNTs/MF is about 184 F g?1 based on the total mass of the composite and 262 F g?1 based on the mass of PPy (70.2 wt % in the composite) at the current density of 0.4 A g?1, which is higher than that of PPy/CNTs/MF (120 F g?1 based on the total mass of the composite and 167 F g?1 based on the mass of the PPy). Furthermore, the capacitor assembled by CNTs/PPy/CNTs/MF shows excellent cyclic stability. The capacitance of the cell assembled by CNTs/PPy/CNTs/MF retains 96.3% over 450 scan cycles at scan rate of 20 mV s?1, which is larger than that assembled by CNTs/PPy/MF (72.5%). © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39779.  相似文献   

15.
Nano-thin polypyrrole (PPy) layers were coated on chemically modified ordered mesoporous carbon (m-CMK-3) by an in situ chemical polymerization. Structural and morphological characterizations of m-CMK-3/PPy composites were carried out using field emission scanning electron microscopy. Pseudo-capacitive behavior of the deposited PPy layers on m-CMK-3 was investigated by cyclic voltammetry, galvanostatic charge-discharge and electrochemical impedance spectroscopy. As results of this study, the thin layer of PPy in the composite electrode was effective to obtain fully reversible and very fast Faradaic reaction. A maximum discharge capacity of 427 F g−1 or 487 F g−1 after correcting for weight percent of PPy phase at the current density of 5 mA cm−2, could be achieved in a half-cell setup configuration for the m-CMK-3/PPy composites electrode, suggesting its potential application in electrode material for electrochemical capacitors.  相似文献   

16.
采用化学气相沉积制备了聚吡咯/超高相对分子质量聚乙烯(PPy/UHMWPE)纤维,测试了不同氧化剂浓度、不同沉积时间和温度下PPy/UHMWPE纤维的表面剪切强度,用扫描电镜、动态热机械分析仪、傅立叶变换红外光谱仪分析了PPy/UHMWPE纤维的表面形态、热机械性能和复合材料官能团的变化。结果表明:PPy均匀分布在UHMWPE纤维表面,UHMWPE纤维与PPy之间无化学键作用而是分子间作用力;随着氧化剂三氯化铁浓度的增加和吡咯沉积时间的延长,PPy/UHMWPE纤维表面剪切强度先增大后减小;随着处理温度的升高,PPy/UHMWPE纤维表面剪切强度先增大,当处理温度超过85℃时,其剪切强度则减小。  相似文献   

17.
Poly(3-octyl-thiophene) (POT) and polypyrrole (PPy) iron oxalate composites were synthesized through a post-polymerization oxidative treatment. The composite of the latter has been prepared also by electrochemical polymerization. The samples have been characterized by X-ray diffraction (XRD), impedance spectroscopy, scanning electron microscope (SEM) combined with energy dispersive X-ray (EDX) spectroscopy, Mössbauer spectroscopy, cyclic voltammetry and electrochemical quartz crystal microbalance (EQCM). In case of PPy, two peaks in the XRD spectra show the presence of iron containing composite, while with POT only the layered structure originating from the octyl side-chain interactions was modified by the composite formation. The assumption of the weakening of short- and long-range interactions was proven by the decrease in conductivity of the composite. The successful electrochemical synthesis resulted a composite of ∼5% iron content, determined by EDX. Mössbauer spectroscopy measurements evidenced a composite containing mixed valence iron oxalate doping ions, which supports the indirect EQCM data.  相似文献   

18.
The composites of polypyrrole/manganese dioxide/polypropylene fibrous films (PPy/MnO2/PPF) have been prepared in situ through chemical oxidation polymerization by using the mixture of FeCl3·6H2O and MnO2 adsorbed on PPF as oxidant in the atmosphere of pyrrole vapor at room temperature. The morphologies and structures of the composites are investigated by using scanning electron microscope and X-ray diffraction spectroscopy. The properties of the capacitor cells assembled by the composites of PPy/MnO2/PPF are evaluated by cyclic voltammetry, galvanostatic charge/discharge and electrochemical impedance spectroscopy methods. The results reveal that the morphologies, conductivities and capacitance performance of the composites are influenced strongly by the content of MnO2 in the solution of oxidant. The capacitors assembled by PPy/MnO2/PPF exhibit the property of quick charge/discharge, and the highest specific capacitance of about 110 F g−1 is obtained when the PPy/MnO2 content in the composite is about 17.4%.  相似文献   

19.
Polymer nanocomposite composed of polypyrrole, chitosan, and zinc oxide nanoparticles has been synthesized and it has been evaluated for various electrochemical aspects of the current electrochemical industry. The polypyrrole (PPy) was synthesized by the chemical oxidative polymerization reaction by employing ammonium persulfate as oxidizing agent. Composites of polypyrrole/chitosan (PPy/Chy) and polypyrrole/chitosan/ZnO (PCZ) composites were synthesized by the solution blending method. Detailed structural, morphological, thermal characterization of PPy, PPy/Chy, and PCZ were performed to characterize the specific features of the systems. The composites exhibit better thermal stability and high surface area and the addition of ZnO nanoparticle increase the crystallinity of the composite. Electrochemical characterization of the ITO electrodes modified with PPy, PPy/Chy, and PCZ were performed using cyclic voltammetry, electrochemical impedance spectroscopy, and amperometry techniques. The present study highlights the role of a bio-compatible material with high surface area and conductive constituent for designing of various high performing electronic noninvasive sensors, biosensors, and so forth.  相似文献   

20.
Polypyrrole (PPy) composites were prepared with both unmodified and amine‐modified multiwalled carbon nanotubes (MWCNTs) in the presence and absence of barium titanate (BaTiO3) by in situ oxidative polymerization. A uniform coating of PPy on the MWCNTs and BaTiO3 surfaces was confirmed by field emission scanning electron microscopy and high‐resolution transmission electron microscopy images. The structure of the pure and amine‐modified MWCNTs were identified by Fourier transform infrared spectroscopy. The incorporation of BaTiO3 enhanced the thermal stability and capacitance properties of the composites. The maximum specific capacitance and energy density values found for the PPy/amine‐modified MWCNT/BaTiO3 composites were 155.5 F/g and 21.6 W h/kg, respectively, at a scan rate of 10 mV/s. The maximum power density was found to be 385.7 W/kg for the same composite at a scan rate of 200 mV/s. Furthermore, the impedance spectra of the composites showed moderate capacitive behavior. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   

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