共查询到19条相似文献,搜索用时 78 毫秒
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用原位聚合法制备了聚吡咯/碳纳米管(PPy/MWNTs)复合物。采用XRD、TGA、FT-IR、SEM、四探针测试仪和网络分析仪表征了PPy/MWNTs复合物的组成、结构、形貌和电性能。研究了不同条件,如质子酸及其浓度、引发剂和单体的物质的量比(nAPS/nPy)、MWNTs的质量分数(ωMWNTs)和反应时间对PPy/MWNTs复合物电性能的影响。结果表明,当磷酸浓度为0.1 mol/L、nAPS/nPy为1:1、ωMWNTs等于45 wt%、反应时间12 h时,制备的PPy/MWNTs复合物的导电性和介电损耗性能最好。 相似文献
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通过原位种子聚合构筑了碲化镉量子点(CdTe QDs)/聚吡咯(PPy)纳米复合物。利用透射电镜、红外光谱及荧光发射光谱对其形貌、结构、光致发光性质进行了测试分析。研究结果表明, 复合物中CdTe量子点结晶良好。复合物中两组分间能级耦合相互作用使量子点表面陷阱态钝化, 从而导致对应CdTe量子点带间跃迁的410 nm发光峰的出现, 显示了复合物作为光电器件材料的潜在应用价值。 相似文献
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针对传感器的敏感单元发展需求,提出了一种碳纳米管复合材料.该材料是以碳纳米管作为填充粒子,结合聚二甲基硅氧烷(PDMS)有机基体,采用超声共混方法制备的一种新型传感器敏感元件.详细分析研究了复合材料的制备工艺参数,以及在不同工艺参数下该复合材料的力敏特性.扫描电镜测试表明碳纳米管在PDMS中分散均匀且镶嵌良好.通过对不同体积分数的碳纳米管与PDMS复合材料进行电学性能测试,研究薄膜的"力-电阻"和"力-电容"耦合性能,测试了薄膜结构的力敏效应.计算得到复合薄膜材料的压阻灵敏度因子达到40,压电容灵敏度因子达到70.实验研究表明,通过改变碳纳米管与PDMS的比例,可以很好地调节其电子输运特性以及电阻和电容的应力敏感特性,可以为该类型的力敏材料在不同的力敏传感技术领域提供新的研究思路. 相似文献
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为了研究磷酸锌二次掺杂聚吡咯/聚噻吩膜的光电及防腐蚀性能,采用直接接触氧化技术在磷酸锌溶液中制备出掺杂聚吡咯/聚噻吩,再用磷酸锌在脱掺杂聚吡咯的基础上制备出性能优良的二次掺杂聚吡咯/聚噻吩膜。采用循环伏安曲线、扫描电镜和动电位极化曲线测试了二次掺杂聚吡咯/聚噻吩/磷酸锌复合材料的微观形貌及光电性能,并与一次掺杂及未掺杂的聚吡咯/聚噻吩进行了对比。测试结果表明:不锈钢表面覆盖掺杂的聚吡咯/聚噻吩膜都有较好的光电性能,以二次掺杂聚吡咯/聚噻吩膜性能为最好。与未掺杂的聚吡咯/聚噻吩高分子膜相比,二次掺杂聚吡咯膜的腐蚀电位比纯聚苯胺膜提高了约0.989 V,自腐蚀电流降低了约2个数量级。 相似文献
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系统地研究了溶剂、温度和聚合电流密度对电化学制备本征导电聚吡咯 (PPy)膜密度的影响,分别用四探针法和热失重(TG)法研究了不同密度的PPy膜的电导率和热稳定性.用循环伏安法(CV)和电化学阻抗谱(EIS)法比较了不同密度的PPy膜的电化学性能.研究表明,在室温下,在乙氰/水(AN/H2O, 99/1)溶液比在水溶液中容易得到高密度的PPy膜.高聚合电流密度(如10mA/cm2)可以进一步提高PPy膜的密度,用X射线光电子能谱(XPS)对其结构进行了分析.在AN/H2O(99/1)溶液中用小电流密度(0.1mA/cm2)聚合时,低温(-20℃)有利于提高PPy膜的密度;然而在高电流密度(10mA/cm2)时, 低温(-20℃)不利于提高PPy膜的密度.高密度的PPy膜(1.42g/cm3)用电流密度10mA/cm2在0℃的AN/H2O(99/1)溶液中制得.该合成方法和常用的低温低电流密度方法制备高密度的PPy膜相比, 合成时间短,条件易实现,更利于实用化.更重要的是,高密度的PPy膜不仅具有高电导率(~220S/cm)和高热稳定性,还具有低的电化学活性.因此,高密度的PPy膜不仅是一种优异的电子导电的电极材料,而且是一种潜在的优异的防腐材料.
关键词:
聚吡咯膜
密度
电导率
热稳定性 相似文献
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共轭导电聚合物经过掺杂,电导率可以提高十几个数量级,由绝缘体变为导体.但是,掺杂对聚合物链结构的影响方面,人们目前尚所知甚少.从实验的角度看,由于物性测量结果和材料的制备过程密切相关,往往不容易重复,有时还会出现一些令人困惑的假象. 相似文献
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测量了液氮温区导电聚吡咯薄膜在直流电场下的电阻,发现电阻对电场有依赖关系。所有的结果在变程跳跃理论上得到很的解释。 相似文献
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Sun-Kuk Kim Jeong Tai Kim Hee-Cheul Kim Kyong-Yop Rhee John Kathi 《Journal of Macromolecular Science: Physics》2013,52(2):358-367
Multi-scale hybrid composite laminates of epoxy/carbon fiber (CF) reinforced with multi-walled carbon nanotubes (MWCNTs) were fabricated in an autoclave. For laminate fabrication, 0.5 wt% of pristine MWCNTs or silane-functionalized MWNCTs (f-MWCNTs) were dispersed into a diglycidyl ether of bisphenol-A epoxy system and applied on the woven carbon fabric. The neat epoxy/CF composite and the MWCNTs-reinforced epoxy/CF hybrid composites were characterized by thermogravimetric analysis (TGA), thermomechanical analysis (TMA), tensile testing, and field emission scanning electron microscopy (FE-SEM). A significant improvement in initial decomposition temperature and glass transition temperature of epoxy/CF composite was observed when reinforced with 0.5 wt% of f-MWCNTs. The coefficient of thermal expansion (CTE), measured by TMA, diminished by 22% compared to the epoxy/CF composite, indicating an improvement in dimensional stability of the hybrid composite. No significant improvement in tensile properties of either MWCNTs/epoxy/CF composites was observed compared to those of the neat epoxy/CF composite. 相似文献
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用物理掺杂工艺将纳米碳管引入二氧化硅凝胶玻璃基质,成功制备了纳米碳管复合凝胶玻璃,采用X射线衍射、透射电子显微镜、紫外-可见吸收光谱、红外光谱、拉曼光谱等测试方法对其结构和谱学性能进行了表征。结果表明,通过优化掺杂工艺能够实现纳米碳管与基质的均匀复合,纳米碳管本身的结构在掺杂过程中并未发生改变。纳米碳管的引入对二氧化硅凝胶玻璃基质的紫外-可见吸收光谱和红外光谱未产生显著影响。 相似文献
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Chaonan Yang 《Journal of Macromolecular Science: Physics》2017,56(10):790-799
A high-performance silicone rubber (SR) composite (denoted as SCT) filled with 5 phr functionalized carbon nanotubes (CNTs) and 40 phr fumed silica (SiO2) was prepared by mechanical blending. The CNTs were functionalized by tetrakis (phenylmethyl)-thioperoxydi (carbothioamide) (TBzTD); it contains four benzene rings that can interact with the CNTs via π–π interactions. Raman spectroscopy and X-ray photoelectron spectroscopy analysis demonstrated the existence of the π-π interactions between the CNTs and the TBzTD. Transmission electron microscopy and scanning electron microscopy confirmed the uniform dispersion of the CNTs in SR matrix and strong interfacial interactions between the SR and the CNTs. The effects of these non-covalently functionalized CNTs on the mechanical properties of the silica filled SR composites were fully investigated. The results showed that the tear strength of the SCT composite with TBzTD functionalized CNTs was significantly improved, by 249%, compared with that of the composite containing only SiO2. An obvious crack deflection occurred in the SCT during the tearing process, resulting in the enhanced tear strength. 相似文献
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Jie Zhang Xian Wu Chao Guo Liangbo Yang Xueqin Gao Hesheng Xia 《Journal of Macromolecular Science: Physics》2013,52(11):2193-2202
To study the effect of vibration field on the electrical conductivity properties of nanocomposites, isotactic polypropylene (iPP)/multiwalled carbon nanotubes (MWCNT) composites were prepared by conventional injection molding and vibration injection molding. Results showed that the electrical conductivity of iPP/MWCNT composites was significantly promoted by vibration injection molding. Vibration injection molded samples had a percolation threshold of about 2.7 wt% compared with the threshold of about 4.5 wt% for conventional injection molded samples. The effects of test locations and vibration frequency on the electrical conductivity of composites were investigated. The samples exhibited an inhomogeneity along the injection direction. The electrical conductivity of the samples was different at different test locations and increased with increasing vibration frequency. Polarized light microscopy (PLM) results indicated that vibration injection molding can induce MWCNT aggregates to be stretched and oriented along the flow direction, which could form conductive networks and greatly enhance the electrical conductivity of iPP/MWCNT composites. 相似文献
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以柠檬酸法制备的Fe MgO、Co MgO和Ni MgO为催化剂 ,CH4 为碳源气 ,H2 为还原气 ,在 873、973和 10 73K制备出碳纳米管 ,通过TEM和拉曼光谱表征 ,讨论了催化剂、制备温度、反应时间等因素对碳纳米管形貌、产率和内部结构的影响 .结果表明 :不同的催化剂在相同的温度下制备的碳纳米管的形态和内部结构有很大的差异 .其中Fe MgO催化剂制备的碳纳米管管径粗 ,且大小不均匀 ,而Ni MgO催化剂制备的碳纳米管管径较细、较均匀 .碳纳米管的产率随着裂解温度的变化而改变 .Fe MgO催化剂制备碳纳米管的产率随制备温度的升高而提高 ,而Ni MgO催化剂制备碳纳米管的产率随制备温度的升高而降低 .Fe MgO催化剂制备碳纳米管 ,在10 73K甚至更高的制备温度才能达到其最高产率 .Co MgO催化剂制备碳纳米管的产率在 973K左右产率较高 ,而用Ni MgO催化剂制备碳纳米管 ,则在 873K甚至更低的制备温度就能达到最高产率 .反应时间与碳纳米管的产率不成正比 ,有一最佳反应时间 ,如Ni MgO催化剂的最佳反应时间为 2h . 相似文献
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表面修饰纳米碳管复合二氧化硅凝胶玻璃的制备研究 总被引:1,自引:0,他引:1
采用羧基化、酰氯化和酰胺化等三步化学反应实现了r-氨基丙基三乙氧基硅烷(NH2(CH2)3Si(OC2H5)3,APTES)对纳米碳管(CNTs)的表面修饰。在此基础上,采用溶胶-凝胶工艺将其引入到二氧化硅凝胶玻璃中,并通过红外IR光谱、扫描电子显微镜SEM分析测试方法对所得样品的组成和结构进行表征。结果表明,经过一系列的化学处理,成功实现了CNTs与APTES的共价键合而达到表面修饰的效果。溶胶-凝胶过程中,先驱液中正硅酸乙酯(Si(OC2H5)4,TEOS)、r-缩水甘油醚基丙基三甲氧基硅烷(CH2OCHCH2O(CH2)3Si(OCH3)3,GPTMS)、CNTs-APTES分别发生水解,并经过共同聚合反应形成二氧化硅三维网络结构,而CNTs也借助于APTES而被化学键合到二氧化硅网络中,实现了在二氧化硅凝胶玻璃基质中的均匀分散,从根本上克服了CNTs在固相基质中团聚的问题。 相似文献
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Ping-An Song Hai-Tang Yang Shen-Yuan Fu Qiang Wu Jie-Wang Ye Feng-Zhu Lu 《Journal of Macromolecular Science: Physics》2013,52(5):907-921
Maleic anhydride grafted polypropylene (PP-g-MA) was employed as the compatibilizer and carbon nanotubes (CNTs) or hydroxylated CNTs as reinforcements for polypropylene/wood flour composites. The results showed that when the PP-g-MA loading level was 10 wt%, the bending strength, tensile strength, Izod notched impact strength, and elongation at break of PP-wood composites were enhanced by 85% (66.3 MPa), 93% (33.7 MPa), 5.8% (2.01 kJ/m2), and 64% (23%), respectively, relative to the uncompatibilized composites. The introduction of pristine CNTs only improved slightly the overall mechanical properties of the compatibilized composites due to poor interfacial compatibility. Unlike CNTs, incorporating hydroxylated CNTs (CNT-OH) could significantly improve all of the mechanical properties; for instance, at 0.5 wt% CNT-OH loading, the flexural strength and tensile strength reached 68.5 MPa, and 40.4 MPa about 6.6% higher than that for the composites with the same CNT loading. Furthermore, CNT-OH also remarkably enhanced the storage modulus. Contact angle and morphology observations indicated that the increases in mechanical properties could be attributed to the improvements of interfacial interactions and adhesions of CNTs with the matrix and fillers. 相似文献
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S. Boukheir Z. Samir R. Belhimria L. Kreit N. Éber 《Journal of Macromolecular Science: Physics》2018,57(3):210-221
The electrical properties of epoxy polymer/carbon nanotubes composites were characterized using impedance spectroscopy in the frequency range between 1 Hz and 10 MHz and temperature range between 25°C and 105°C. We report the analysis of the experimental data using the electric modulus formalisms to understand the dielectric relaxation mechanisms. The variation of the real and imaginary parts of the electric modulus versus frequency and temperature were suggestive of two relaxation processes, associated with dipolar relaxation and CNT-polymer interfaces. The Havriliak-Negami model of dielectric relaxation was used for modelling the relaxation processes, extracting the relaxation parameters. 相似文献