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71.
The degradation behaviour of electrochemically prepared polythiophene and polypyrrole has been studied by thermal gravimetric
analysis technique. Studies on both the polymers show that they are more stable than polyacetylene but still undergo degradation
reactions which involve two steps, viz. loss of dopant and then degradation of polymer backbone. The general features of degradation
mechanisms are discussed. 相似文献
72.
A metallic polypyrrole film has been directly formed on a p‐type Si substrate by means of an anodization method under conditions of constant current density by an electrolyte being held at a constant temperature of 55°C that was composed of 0.40M pyrrole and 0.10M tetrabutylammonium tetrafluoroborate. An aluminum electrode was used as an ohmic contact. The polypyrrole/p‐Si/Al structure has clearly demonstrated rectifying behavior by the current–voltage curves studied at room temperature. The capacitance–voltage–frequency curves of the structure have been measured at different frequencies at room temperature in dark. To observe the effect of the aging, the measurements were also repeated 7, 15, 30, 60, and 90 days after fabrication of the polypyrrole/p‐Si/Al Schottky diode. During the whole measurement process, the probe of holder on sample was fixed to eliminate effects of surface inhomogeneity. The interface state density distribution curves of device have been obtained from forward bias current–voltage (I‐V) and capacitance–frequency (C‐f) characteristics as a function of aging time. From these curves, the exponential growth of the interface‐state density from midgap toward the top of the valence band is very apparent. The shape of the interface state density distribution curves from the forward bias I‐V characteristics are very similar to those obtained from C‐f. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 2313–2319, 2006 相似文献
73.
74.
75.
PPy/SiO2纳米复合材料的合成与导电性能 总被引:6,自引:0,他引:6
以乙醚反应介质,用化学方法合成了聚吡咯纳米复合材料,利用红外光谱,四探针技术和透射镜表征了这些材料的组成,结构和导电性能,结果表明,载流子在PPy分子链之间和PPy聚集体之间有的传导性。 相似文献
76.
导电聚合物型超电容器的比较研究 总被引:2,自引:0,他引:2
以掺杂聚(3 甲基噻吩)、掺杂聚吡咯或碳纳米管为活性物质,以偏氟乙烯 六氟丙烯共聚物为粘结剂,以乙炔黑为添加剂,将它们均匀混合后制成电极材料,再以LiClO4的1,4 丁内酯溶液为非水系电解质,以偏氟乙烯 六氟丙烯共聚物制成的微孔膜作隔膜,分别组装了Ⅰ型氧化还原超电容器、Ⅱ型氧化还原超电容器和新型的氧化还原 双电层混合型超电容器。并对上述超电容器进行了循环伏安与恒电流充放电测试。对它们的比较研究表明:Ⅱ型氧化还原超电容器具有较高的比能量(可达8.7Wh/kg),混合型超电容器则具有较高的比功率。这两种超电容器具有潜在的使用价值。 相似文献
77.
78.
Peter R. Teasdale Hailin Ge Kerry Gilmore Gordon G. Wallace 《Polymer International》1992,29(4):299-305
A new method for characterizing conducting polymers, based on thin layer chromatography, is evaluated. Polypyrrole and polyaniline were used as the stationary phase and molecular probes were used to characterize favourable interactions on the polymers. Amino acids were chosen as the molecular probes because of the range of properties they exhibit and because there are numerous methods for their detection. Some difficulties were experienced in preparing stationary phases with suitable physical properties. However, once this was overcome, useful information was obtained with inverse TLC. Polypyrrole and polyaniline were both found to behave predominantly as anion-exchange materials. 相似文献
79.
Richard Akinyeye Mantoa Sekota Priscilla Baker Emmanuel Iwuoha 《Fullerenes, Nanotubes and Carbon Nanostructures》2006,14(1):49-55
A preliminary result of the morphology and yield of chemically synthesized polypyrrole (PPY) using β-naphthalene sulfonic acid (NSA) and ammonium peroxodisulphate (APS) in aqueous medium is presented. Various micro/nanotubes were obtained using different dopant/monomer (D/M) ratios and temperature settings. Similar but shorter and sheet-like nanostructures were obtained without the use of surfactant NSA; with a fibre-like, loose and admixed physical outlook. The percentage yield (m/v) of the doped PPY was greater than that from the undoped, being 27-44 and 18-20, respectively with higher values obtained from the low temperature synthesis. The highest percentage yield of 44 was obtained from a D/M ratio of 0.8. 相似文献
80.
It is shown that porous materials such as paper can be impregnated with a conducting polymer by first soaking the paper in
a solution of metal salt which acts as an initiator for subsequent polymerization. By using this procedure the conductivity
of filter paper can be raised to as high as 2 (ohm cm)−1 for an FeCl3/H20/pyrrole combination. The role of the metal ion is discussea and it is pointed out that the impregnated papers exhibit both
ionic and electronic conductivity. The polypyrrole paper composites exhibit some properties similar to carbon black-polymer
composites. 相似文献