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1.
C. M. Chao G. P. Wang K. H. Wu T. C. Chang 《Journal of Polymer Science.Polymer Physics》2006,44(1):1-8
A novel conductive blend of polyaniline (PANI) with polyamidoamine dendrimer (PAMAM (G 2.0)) was prepared by different blending procedure. The PANI‐PAMAM blended polymers were characterized by UV–vis, FTIR, and electron paramagnetic resonance (EPR) spectra. The effect of varying the blending procedure on structure and EPR properties of PANI‐PAMAM blended polymers was investigated. Varying the blending procedure and temperature has a direct effect on the structure and EPR parameters (ΔHPP, g factor, NS, T2, and A/B ratio). EPR spectroscopic studies suggested the presence of chemical interaction between PANI and PAMAM. Electron localization effects in PANI‐PAMAM blended polymers can therefore be studied using the technique of EPR. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 1–8, 2006 相似文献
2.
Electrical conductivity change of polyaniline–dodecyl benzene sulfonic acid complex with temperature
Polyaniline–dodecylbenzene sulfonic acid (PAn–DBSA) complex was thermally treated and its conductivity and structure change were investigated. The conductivity increased linearly from 1.1 × 10−4 to 3.0 × 10−1 S/cm on thermal heating until 140°C, but decayed above 200°C. The increase was caused by an additional thermal doping resulting from an increasing mobility of undoped dopants. After the thermal doping, the formation of the layered structure of PAn–DBSA is made. The decrease was caused by the thermal decomposition of dopants. The conductivity changes at a high temperature was strongly dependent on the nature of the dopant. The results were confirmed by means of X-ray patterns and Fourier transform infrared spectra obtained in the heating and cooling processes of polyaniline. 相似文献
3.
This work reports on a new class of dopants, benzoic acid and substituted benzoic acids such as 2‐hydroxybenzoic acid, 2‐chlorobenzoic acid, 4‐nitrobenzoic acid, 2‐methoxybenzoic acid, 3‐methylbenzoic acid, 4‐methylbenzoic acid, 3‐aminobenzoic acid and 4‐aminobenzoic acid, for polyaniline. Benzoic acids can be used to dope polyaniline by mixing benzoic acid (or a substituted benzoic acid) with polyaniline in the common solvent 1‐methyl‐2‐pyrrolidone. Properties of benzoic acid doped polyaniline salts are studied using Fourier transform infra‐red, X‐ray diffraction spectroscopy, scanning electron microscopy, thermogravimetric analysis and conductivity measurements. The conductivity of polyaniline‐benzoic acid salt was found to be high (10−2 S/cm) when compared to polyaniline‐substituted benzoic acid salts (10−3–10−5 S/cm). Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
4.
5.
C. Basavaraja Y. Veeranagouda Kyoung Lee R. Pierson Do Sung Huh 《Journal of Polymer Science.Polymer Physics》2009,47(1):36-45
Conducting polyaniline‐polymannuronate (PANI‐PM) composites were synthesized via in situ deposition techniques. By dissolving different weight percentages of polymannuronate (PM) (5, 10, 15, and 25%), the oxidative polymerization of aniline was achieved through the use of ammonium persulfate as oxidant. Structural morphology, FT‐IR, and X‐ray diffraction (XRD) studies support a strong interaction between PANI and PM. The temperature‐dependent DC conductivity of PANI‐PM composites was studied within the range of 300 ≤ T ≤ 500 °K, presenting evidence for the transport properties of PANI‐PM composites. Conductivity was analyzed through Mott's equation, which leveraged the variable range hopping model in three dimensions. Parameters such as density of states at the Fermi energy, hopping energy, and hopping distance were calculated. Based on the above factors, the synthesis of PANI‐PM composites envisages the future development of biomimetic materials for the creation of a new bionanocomposite as a multicomponent and multifunctional material. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 36–45, 2009 相似文献
6.
Catalytic behaviors of silica‐supported natural biopolymer–oxalic acid–Pt complexes in hydrogenation
Three kinds of natural biopolymers, gelatin, alginic acid and sodium carboxymethylcellulose (NaCMC), were reacted with oxalic acid in the presence of silica to yield complexes on the surface of silica, followed by reaction with H2PtCl6 6H2O to form Pt complexes, SiO2–gelatin–(COOH)2–Pt, SiO2–alginic acid–(COOH)2–Pt, and SiO2–NaCMC–(COOH)2–Pt, respectively. These complexes were able to catalyze the hydrogenation of 1‐heptene to give n‐heptane and that of nitrobenzene to give aniline at 25 °C and under 1 atm H2 in 100% yields. Experimental data show that the catalysts were very stable and could be reused without any remarkable change in catalytic activity. Copyright © 2000 John Wiley & Sons, Ltd. 相似文献
7.
《Journal of Coordination Chemistry》2012,65(17):2796-2803
Direct reaction of pyridine-3,5-dicarboxylic acid (H2PDA) and oxalic acid (H2ox) with Ln(ClO4)3 · nH2O under hydrothermal conditions gave three 3-D coordination networks, [Ln(PDA)(ox)0.5(H2O)2] · H2O [Ln = La(1), Nd(2), and Eu(3)]. The complexes were characterized by elemental analysis (EA), X-ray single-crystal diffraction, infrared spectroscopy (IR), and thermogravimetric analysis (TGA). Single crystal X-ray diffractions shows that the compounds are isomorphous and have 3-D framework structures, in which pyridine-3,5-dicarboxylates (PDA2?) link lanthanides to give 2-D layers, which are further fabricated into a 3-D network via bis-bidentate oxalate bridging. Luminescence of 3 is investigated. 相似文献
8.
L-磺基丙氨酸的电化学合成及表征 总被引:3,自引:0,他引:3
L 磺基丙氨酸是一种重要的生化试剂 ,在医药、化妆品、洗涤剂等行业应用广泛 ;目前主要是采用过氧化物、二甲亚砜、溴等氧化L 胱氨酸制备它[1 ,2 ] ,我们尝试采用间接电氧化法合成 ,其特点是在电化学合成时 ,氧化媒质循环利用 ,避免了使用较贵的氧化剂 ,省去了还原产物的后处理 ,工艺简单 ,成本低 ,产物纯度高 ,而且无“三废”排放 ,与化学合成法相比有明显优势。1 实验部分1 1 主要实验仪器M 1 730红外光谱仪 ;FX90Q核磁共振波谱仪 ;TGA 7型热重分析仪 ;CDR 1型差动热分析仪。1 2 L 磺基丙氨酸的电化学合成在自制H型电… 相似文献
9.
Density functional theory, B3LYP/6‐31G** and B3LYP/6‐311+G(2d,p), and ab initio MP2/6‐31G** calculations have been carried out to investigate the conformers, transition states, and energy barriers of the conformational processes of oxalic acid and its anions. QCISD/6‐31G** geometrical optimization is also performed in the stable forms. Its calculated energy differences between the two most stable conformers are very near to the related observed value at 7.0 kJ/mol. It is found that the structures and relative energies of oxalic acid conformers predicted by these methods show similar results, and that the conformer L1 (C2h) with the double‐interfunctional‐groups hydrogen bonds is the most stable conformer. The magnitude of hydrogen bond energies depends on the energy differences of various optimized structures. The hydrogen bond energies will be about 32 kJ/mol for interfunctional groups, 17 kJ/mol for weak interfunctional groups, 24 kJ/mol for intra‐COOH in (COOH)2, and 60 kJ/mol for interfunctional groups in (COOH)COO−1 ion if calculated using the B3LYP/6‐311+G(2d,p) method. © 2000 John Wiley & Sons, Inc. Int J Quant Chem 76: 541–551, 2000 相似文献
10.
SHEN Yi ZHU Hua HUANG Rong ZHAO Li & YAN ShaNing Faculty of Material Science Chemical Engineering China University of Geosciences Wuhan China Faculty of Materials Science Engineering Hubei University Wuhan 《中国科学B辑(英文版)》2009,(5)
Tungsten trioxide powder with the novel morphology was prepared via the hydrothermal method with oxalic acid as the organic inducer, the structure and shape of which were detected by X-ray diffraction (XRD), scanning electron microscopy (SEM) and BET. Furthermore, photochromic properties of the as-prepared powder samples were tested by an ultraviolet-visible spectrophotometer combined with a color difference meter. The corresponding results indicated that the induced product was still hexagonal WO3, made up... 相似文献
11.
草酸改性空气凤梨生物炭吸附甲醛的机理研究 总被引:1,自引:0,他引:1
探究草酸改性园林废弃物类生物炭对溶液中甲醛的吸附效率和固定的机理,为园林废弃物类生物炭在甲醛污染控制方面的应用提供科学依据.利用马弗炉在低氧条件下将空气凤梨原材料和草酸改性后的原材料制备成生物炭.然后利用实验室模拟法,研究不同反应时间、甲醛浓度、pH对生物炭吸附效果的影响,并分析草酸改性如何提高园林废弃物类生物炭对甲醛... 相似文献
12.
C. Basavaraja R. Pierson T.K. Vishnuvardhan Do Sung Huh 《European Polymer Journal》2008,44(5):1556-1566
Polymer composites containing polyaniline–poly-N-isopropylacrylamide-co-acrylic acid/alumina (PANI–PNA/Al2O3) were synthesized by chemical polymerization of aniline in an aqueous solution containing dispersed PNA/Al2O3 in the presence of dodecylbenzene sulfonic acid (DBSA) using different wt% of Al2O3 (5%, 10%, 20%, and 30%). The structure and morphology of the polymer matrix were identified by scanning electron microscope (SEM) and atomic force microscope (AFM). Thermal stability and an amended crystallinity were reasserted by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and X-ray diffraction (XRD), respectively. Chemical interaction of Al2O3 and PANI was characterized by XPS. The enhancement of the electrical conductivity in the temperature range 293–483 K shows a semiconducting behavior with a negative temperature coefficient of resistivity (TCR). In addition, the conductivity data are characterized by three different regions with small changing jerks with increasing temperature. 相似文献
13.
Vilmos Fülöp Alajos Kalman Rainer Beckert Jürgen Fabian 《Monatshefte für Chemie / Chemical Monthly》1989,120(6-7):561-569
Summary The action of bisimidochlorides of oxalic acid on dithiocarbamates produces 2-thioxo-3-aryl(alkyl)-4,5-diiminothiazolidines by cycloacylation. The molecular structure of 2-thioxo-3-(4-methoxyphenyl)-4,5-bis(phenylimino)-thiazolidine is confirmed by X-ray crystal structure analysis.
Zur Reaktion von Dithiocarbaminaten mit stickstoffhaltigen Derivaten der Oxalsäure
Zusammenfassung Bei der Einwirkung von Bisimidchloriden der Oxalsäure auf Dithiocarbaminate entstehen durch Cycloacylierung 2-Thioxo-3-aryl(alkyl)-4,5-diiminothiazolidine. Die Molekülstruktur von 2-Thioxo-3-(4-methoxyphenyl)-4,5-bis(phenylimino)thiazolidin wird durch Röntgenkristallstrukturanalyse bestätigt.相似文献
14.
Tungsten trioxide powder with the novel morphology was prepared via the hydrothermal method with oxalic acid as the organic
inducer, the structure and shape of which were detected by X-ray diffraction (XRD), scanning electron microscopy (SEM) and
BET. Furthermore, photochromic properties of the as-prepared powder samples were tested by an ultraviolet-visible spectrophotometer
combined with a color difference meter. The corresponding results indicated that the induced product was still hexagonal WO3, made up of regularly spindle particles with 200–300 nm in length and 30–50 nm in width. The ratio of the length and width
was from 4 to 10. Moreover, the special morphology improved its absorptive capacity to the excitation light source, resulting
in its high photochromic properties.
Supported by the National Natural Science Foundation of China (Grant No. 50702052) and the Hubei Province Key Laboratory of
Macromolecular Material 相似文献
15.
Polyaniline–CaTiO3 composites of different weight percentages were prepared by in situ polymerization. The prepared composites were characterized by Fourier transform infrared spectroscopy for structural studies, and a morphology analysis was carried out by scanning electron microscopy studies. Real and imaginary parts of the complex impedance were determined for given samples as a function of frequency. Current–voltage and capacitance–voltage measurements were also carried out. The carrier mobility μ values of neat polyaniline and polyaniline–CaTiO3 composites were found to be 5.37 × 10?3 and 2.73 × 10?2, respectively, and a significant enhancement, as compared with the reported data, was observed. Therefore, this study may provide a better route for technological applications in all fields in the near future and can also be represented by a pure electronic model. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
16.
Mohammad Rezaul Karim Jeong Hyun Yeum Min‐Young Lee Mu Sang Lee Kwon Taek Lim 《先进技术聚合物》2009,20(7):639-644
Sulfonated polyaniline‐silver (SPAni‐Ag) hybrid nanocomposites have been synthesized by the in situ reduction using a UV‐curing polymerization method without using any reducing or binding agent. An aqueous solution of aniline and orthoanilinic acid (OA) comonomers, a free‐radical oxidant and silver metal salts were irradiated by UV rays. Reduction of the silver salt in aqueous aniline and OA leads to the formation of silver particles which in turn catalyze the oxidation of comonomers to sulfonated polyaniline (SPAni). The resultant SPAni‐Ag nanocomposites were characterized by using different spectroscopy analyses like UV–visible (UV–Vis), X‐ray diffraction (XRD) and infrared spectroscopy. The absorption bands were revealed to be optically active and the peaks blue‐shifted due to the presence of metallic silver within the SPAni matrix. The XRD patterns displayed both the broad amorphous polymeric and sharp metallic peaks. Scanning electron microscopy and transmission electron microscopy of the nanocomposites showed a uniform size distribution with spherical and granular morphology. Thermogravimetric analysis revealed that the nanocomposites had a better thermal stability than the bulk SPAni. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
17.
Stable suspensions of carbon nanoparticles in polyaniline solutions in N-methylpyrrolidone were compared with the suspensions in aqueous solutions of cetyltrimethylammonium bromide using spectrophotometry in UV— Vis—NIR regions. Polyaniline in low concentrations in N-methylpyrrolidone was found to be a more efficient surfactant than cetyltrimethylammonium bromide in water. Analysis of the optical spectra of suspensions of carbon soots in solutions of the polymer made it possible to reveal a noticeable change in the spectra of the starting polyaniline and nanotubes, indicating the chemical interaction of polyaniline with the carbon nanotubes.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2584–2588, December, 2004. 相似文献
18.
K. G. Neoh E. T. Kang S. H. Khor K. L. Tan 《Journal of polymer science. Part A, Polymer chemistry》1989,27(13):4365-4374
Polyaniline–tetracyanoethylene (TCNE) complexes can be synthesized either from emeraldine base or emeraldine hydrochloride by a relatively simple method. The complexes demonstrate greater stability than the emeraldine hydrochloride at elevated temperatures and under high current densities. The electrical conductivity of the complexes synthesized from emeraldine base can be varied from < 10?6 to 0.2 S/cm by varying the amount of TCNE incorporated. The complexes synthesized from emeraldine hydrochloride are slightly more conductive than the starting emeraldine hydrochloride. In both types of complexes, it appears that electron transfer between the polyaniline and TCNE has occurred resulting in the formation of some positively charged polyaniline nitrogen and TCNE anions. 相似文献
19.
Fourteen new complexes with the general formula of Ln(Hmna)3·nH2O (n=2 for Ln=La-Ho and n=1 for Er-Lu, H2mna=2-mercaptonicotinic acid) were synthesized and characterized by elemental analyses, IR spectra and thermogravimetric analyses.
In addition, molar specific heat capacities were determined by a microcalorimeter at 298.15 K. The IR spectra of the prepared
complexes revealed that carboxyl groups of the ligands coordinated with Ln(III) ions in bidentate chelating mode. Hydrated
complexes lost water molecules during heating in one step and then the anhydrous complexes decomposed directly to oxides Ln2O3, CeO2, Pr6O11 and Tb4O7. The values of molar specific heat capacities for fourteen solid complexes were plotted against the atomic numbers of lanthanide,
which presented as ‘tripartite effect’. It suggested a certain amount of covalent character existed in the bond of Ln3+ and ligands, according with nephelauxetic effect of 4f electrons of rare earth ions. 相似文献
20.
Relative viscosities for the solutions of oxalic acid and its salts, viz. ammonium oxalate, sodium oxalate and potassium oxalate,
at different concentrations have been determined in water and in binary aqueous mixtures of tetrahydrofuran (THF) [5, 10,
15 and 20% by weight of THF] at 298.15 K, and in water and in 5% (w/w) THF + water at five different temperatures. The data
have been evaluated using the Jones-Dole equation and the obtained parameters have been interpreted in terms of solute-solute
and solute-solvent interactions. The activation parameters of viscous flow have been obtained which depicts the mechanism
of viscous flow. The oxalic acid and its salts behave as structure breakers in water and in binary aqueous mixtures of THF. 相似文献