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在恒定磁场(0.8T) 和无磁场环境下,采用化学氧化聚合法合成了分别用磺基水杨酸(SSA)、对甲基苯磺酸(TSA)以及用十二烷基苯磺钠/盐酸(SDBS HCl)掺杂的聚苯胺盐,并采用X射线光电子能谱(XPS)、傅立叶红外光谱(FT-IR)、X粉末衍射(XRD),热重分析(TGA)等手段研究了磁场对聚苯胺结构、掺杂行为及热稳定性的影响.结果表明在合成聚苯胺的过程中,作为表面活性剂的十二烷基苯磺酸钠在无机酸存在条件下转变成十二烷基苯磺酸并与无机酸共同掺杂进入聚苯胺链;磁场环境下合成的聚苯胺盐比无磁场下合成的聚苯胺盐的链更加规整,热稳定性更好,掺杂程度以及结晶性能也有所提高;从红外光谱分析中可知,磁场取向作用使分子链更加伸展,分子链离域程度更大,但磁场没有明显地改变聚苯胺的基本单元结构. 相似文献
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掺杂态聚苯胺的XPS研究 总被引:1,自引:0,他引:1
对经不同质子酸盐酸 (HCl)、对甲基苯磺酸 (TSA)及磺基水杨酸 (SSA)掺杂的聚苯胺 (PAn)进行 3h空气浴的热处理 ,并用电导率和 XPS对其进行了表征。结果表明 ,PAn·HCl在 16 0℃时其电导率下降了六个数量级 ,其表面掺杂率随温度的升高而降低 ,并且具有不同结合能 Cl的相对组成也随之发生了变化 ;PAn·TSA及 PAn·SSA在 2 0 0℃的电导率分别下降了两个和一个数量级 ,但其表面掺杂率未发生明显的变化。随着温度的升高 ,掺杂态 PAn膜的脆性和表面氧化的程度增加 相似文献
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以磺基水杨酸作为掺杂剂,在磁场环境中对聚苯胺进行再掺杂,探讨了磁场强度、掺杂剂浓度和掺杂时间对再掺杂聚苯胺的导电性、溶解性和热稳定性能的影响,并通过四探针、热重分析(TGA)、紫外可见光谱(uV-Vis)以及X-射线衍射(XRD)对再掺杂聚苯胺性能进行了表征。结果表明:在磁场环境中,由于磁场和掺杂酸对聚苯胺,性能影响的协同效应,导致聚苯胺的电导率、溶解性和热稳定性得到了明显的改善,结晶度也得到了很大提高。与无磁场相比,其电导率从0.5s/cm增加到了3.2s/cm,在二甲苯中的溶解度也从12%提高到23%,热分解温度从220℃提高到320℃。 相似文献
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研究了一种聚苯胺衍生物聚邻乙氧基苯胺(POEA),以探讨取代基对聚苯胺聚合、掺杂、溶解的影响.通过化学氧化合成及重掺杂手段,制备了盐酸(HCl)、磺基水杨酸(SSA)、樟脑磺酸(CSA)、对甲苯磺酸(PTSA)等掺杂的聚邻乙氧基苯胺.以GPC、紫外、红外、XRD、四探针等测试手段,对不同掺杂态、脱掺杂态POEA进行了对比分析,同时考察了POEA在不同溶剂下的溶致变色行为.研究表明:脱掺杂态POEA数均分子量为62 834,掺杂后电导率达10-5~10-3S/cm,在常用有机溶剂中有良好的溶解性.随不同的氧化、掺杂程度,POEA溶液呈现红-蓝-绿-黄色的渐变历程,其极化子跃迁峰在494~880 nm移动. 相似文献
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手性聚苯胺的制备及其电磁学性能研究 总被引:1,自引:0,他引:1
采用二次掺杂法制备了具有手征特性的聚苯胺,利用傅立叶红外光谱(FT-IR)、X射线衍射仪(XRD)、圆二色谱仪(CD)和紫外一可见光分光光度计(UV-vis)等分析手段对聚苯胺的结构、性能和手征特性进行了表征.结果表明,通过过硫酸铵作引发剂、盐酸掺杂获得了导电的盐酸掺杂态聚苯胺(PANI-HCI);通过氨水脱掺杂后得到本征态聚苯胺(EB),EB通过手性樟脑磺酸(CSA)诱导,形成了手征性螺旋构型聚苯胺.电磁性能测试表明,与非手性聚苯胺相比,手性聚苯胺具有较优越的吸波性能. 相似文献
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通过化学氧化法分别制备盐酸,盐酸和十二烷基苯磺酸,碳纳米管(MWNTs-COOH)掺杂的聚苯胺,利用红外光谱,紫外光谱,扫描电子显微镜和透射电子显微镜对所制备聚苯胺的结构和形貌进行分析。分析不同掺杂物对聚苯胺的结构和形貌的影响;同时研究了超声波作用对聚苯胺形貌以及聚苯胺包裹MWNTs-COOH情况的影响。 相似文献
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采用不同浓度的盐酸掺杂聚苯胺,采用原位聚合的方法让聚苯胺生长在PVA/Paam复合的多网络水凝胶上,探究最佳掺杂浓度下复合多网络水凝胶的电化学性能,压敏性能和光敏性能。通过红外吸收光谱,紫外吸收光谱,扫描电镜和X射线衍射对聚苯胺粉体进行表征;通过充放电测试,循环伏安法测试,计时电流法,电位溶出分析法,不同波长单色光照射对复合多网络水凝胶进行性能测试。在电化学测试中,确定了在盐酸掺杂浓度为0.5 mol/L时,多网络水凝胶超级电容器的电化学性能最好,充放电时间最长,面积比电容为412.5 mF/cm2。在压力敏感性能测试中,得到具有明显峰性的I-T,V-T曲线,且峰型的振幅和周期与运动强度和频率一一对应。在光敏感性测试中,确定了掺杂盐酸0.35 mol/L时多网络水凝胶具有最佳的光敏感性。说明试验制备的水凝胶同时具有很好的电化学性能、压敏性能和光敏性能,在超级电容器,光敏材料和传感器领域的应用上具有广大的前景。 相似文献
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采用沉淀聚合法,在聚乙二醇的乙醇溶液中制备了钒钛酸掺杂的聚苯胺,并对其进行红外表征和灵敏度、湿滞、电阻特性、电容特性和响应-恢复等湿敏特性研究。结果表明,钒钛酸已掺杂到聚苯胺中,且钒钛酸掺杂聚苯胺的湿敏性能明显优于聚苯胺。当频率为1kHz时该湿敏元件的线性度较好。在11%~97%相对湿度(RH)范围内,电阻变化了3个数量级、灵敏度较高、湿滞回差为5%RH,响应时间为5s,恢复时间为19s,是一种良好的湿敏材料。 相似文献
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The effect of carbon nanotube dispersion on CO gas sensing characteristics of polyaniline gas sensor
Wanna Y Srisukhumbowornchai N Tuantranont A Wisitsoraat A Thavarungkul N Singjai P 《Journal of nanoscience and nanotechnology》2006,6(12):3893-3896
Polyaniline is one of the most promising conducting polymers for gas sensing applications due to its relatively high stability and n or p type doping capability. However, the conventionally doped polyaniline still exhibits relatively high resistivity, which causes difficulty in gas sensing measurement. In this work, the effect of carbon nanotube (CNT) dispersion on CO gas sensing characteristics of polyaniline gas sensor is studied. The carbon nanotube was synthesized by Chemical Vapor Deposition (CVD) using acetylene and argon gases at 600 degrees C. The Maleic acid doped Emeradine based polyaniline was synthesized by chemical polymerization of aniline. CNT was then added and dispersed in the solution by ultrasonication and deposited on to interdigitated AI electrode by solvent casting. The sensors were tested for CO sensing at room temperature with CO concentrations in the range of 100-1000 ppm. It was found that the gas sensing characteristics of polyaniline based gas sensor were considerably improved with the inclusion of CNT in polyaniline. The sensitivity was increased and response/recovery times were reduced by more than the factor of 2. The results, therefore, suggest that the inclusion of CNT in MA-doped polyaniline is a promising method for achieving a conductive polymer gas sensor with good sensitivity, fast response, low-concentration detection and room-operating-temperature capability. 相似文献
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在超声辐照条件下,以HCl为掺杂剂、(NH4)2S2O8为氧化剂,通过溶液聚合得到了HCl掺杂聚苯胺(PA-NI)纳米棒.采用傅里叶变换红外光谱(FTIR)、透射电子显微镜(TEM)、X-射线衍射(XRD)、四电极电导率仪、热重分析(TGA)和电化学工作站对材料的结构与性能进行研究.研究结果表明,超声辐照条件下HCl掺杂PANI具有较高的掺杂程度和结构规整度,形成直径为50~65 nm左右的纳米棒状结构.与传统方法相比,超声辐照法所得材料的热稳定性在270~500℃有明显上升,室温电导率升至0.25 s/cm,并具有较好的电容行为和较高的电化学活性. 相似文献
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Doped polyaniline materials with metal oxalate complexes of Cr, Fe, Mn, Co and Al were synthesized byin situ chemical oxidative polymerization of aniline using potassium perdisulphate as oxidant in aqueous sulphuric acid medium. These
polymer materials were characterized by chemical analyses, spectral studies (UV-visible and IR), X-ray diffraction and thermal
techniques and also by conductivity measurements by four-probe technique. The presence of complex anion in polyaniline material
was confirmed by chemical and spectral analyses. The yield and conductivity of metal oxalate doped polyanilines were found
to be high when compared to the simple sulphate ion doped polyaniline prepared under similar condition. UV-visible and IR
spectral features not only confirmed the polyaniline doping by complex anions but also substantiated their facilitating effect
on conductivity. The X-ray diffraction patterns indicated some crystalline nature in metal oxalate doped polyaniline and amorphous
in polyaniline sulphate salt. The conductivity of the polymer samples strongly depended on the degree of crystallinity induced
by complex counter anions as dopant. All the polymer materials, as evident from TGA curves, were observed to undergo three-step
degradation of water loss, de-doping and decomposition of polymer. Further, the thermal stability of polyaniline was found
to improve on doping with metal oxalate complex. 相似文献
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采用直接混合法,在酒石酸体系下合成一次掺杂聚苯胺纳米材料,经氨水解掺杂后,再用单宁酸对其进行二次掺杂制备出单宁酸二次掺杂聚苯胺材料,解决了单宁酸体系下苯胺无法有效聚合制备聚苯胺的难题。通过扫描电镜、红外光谱及紫外光谱测试对产物进行了表征,利用电化学工作站测试了不同聚苯胺薄膜对Q235碳钢的防腐蚀性能。结果表明,通过二次掺杂方法,单宁酸能有效地掺杂到聚苯胺中,获得形貌良好的纳米纤维;单宁酸二次掺杂聚苯胺能较长时间有效地保护金属基材,其防腐蚀效率最高可达86.02%,在天然海水中浸泡7 d后仍能保持在78.84%。 相似文献
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Doping effect of polyaniline/MWCNT composites on capacitance and cyclic stability of supercapacitors
Karthikeyan G Sahoo S Nayak GC Das CK 《Journal of nanoscience and nanotechnology》2012,12(3):2704-2710
Polyaniline doped by Zn2+ ions was synthesized as nanocomposites with multiwalled carbon nanotubes (MWCNT) by in-situ oxidative polymerization and investigated as electrode material for supercapacitors. The uniform coating of polyaniline on MWCNT was characterized by field emission scanning electron microscopy (FESEM) and high resolution transmission electron microscopy (HRTEM). The effect of Zn2+ ions on nanocomposites were characterized by Fourier transform infrared (FTIR) spectroscopy. The electrochemical performances were investigated by cyclic voltammetry (CV), constant current charging/discharging cyclic test (CC) and electrochemical impedance spectroscopy (EIS) using a three-electrode system. The doped polyaniline composites show higher specific capacitance and better cyclic stability. 相似文献