Search results for "Aniline"
showing 10 items of 259 documents
9-Methyl-3-phenyldiazenyl-9H-carbazole: X-ray and DFT-calculated structures
2006
The title compound, C19H15N3, was prepared by condensation of 3-nitrosocarbazole and aniline with subsequent methylation. The structure is built up of stacks of almost planar molecules. Density functional theory (DFT) calculations predict a completely planar conformation, different from that observed in the crystal lattice. HOMA (harmonic oscillator model of aromaticity) indices, calculated for three aromatic rings, demonstrate the small influence of the azo substituent on π electrons in the carbazole system.
Structure of doped polyaniline - dielectric spectroscopy measurements
1993
The role of doping reagents (residual water and acid anions) in determining the electric properties of a chemically synthesized polyaniline (PANI) was studied using a dielectric spectroscopy method. Dependencies of dielectric losses and susceptibility of PANI as the functions of temperature (-100÷+100°C) and electric field frequency (0.3÷30000 Hz) were examined at it was shown the role of water acts as a doping impurity similar to acid anions. The model is proposed to explain the role of water in terms of adsorption of H 2 O molecules at nitrogen sites of PANI chain and their dissociation
N-Methyl-3-methylsulfonyl-N-nitroaniline
2005
In the title compound, C8H10N2O4S, the N—N bond length [1.3488 (18) A] indicates some double-bond character, while the torsion angle between the aromatic ring and the nitramine group [66.3 (2)°] rules out further delocalization in the molecule. The geometry of the methylsulfonyl substituent is quasi-tetrahedral, as expected. The crystal packing is stabilized by C—H⋯O hydrogen bonds, with the molecules arranged in chains extended along the [101] direction.
Molecular structure of p -methylaniline and its van der Waals complexes with CF 3 H, CH 4 and CF 4 studied by laser induced fluorescence spectroscopy…
2002
The UV fluorescence excitation and dispersed fluorescence spectra of jet-cooled p-methylaniline have been obtained for the S1←S0 transition. The main spectral bands have been assigned by comparison with those of other relevant substituted benzenes and with the help of computed vibrational frequencies. The structure of p-methylaniline in both the S0 and S1 states has been studied at ab initio quantum chemical calculations at MP2 and CIS levels of theory using the 6-31+G∗ basis sets. Both low- and high-resolution laser induced fluorescence spectra of p-methylaniline van der Waals complexes with CF3H, CH4 and CF4 have been characterised following jet-expansion investigations. The equilibrium g…
Polarized IR Spectra of p-Nitroaniline-Loaded AlPO4-5 Single Crystals
1995
Colorimetric determination of arylamines and sulphonamides by diazotization and coupling in a micellar solution
1989
Abstract The use of a micellar solution as a means for improving the colorimetric determination of arylamines by diazotization and coupling is studied. Sodium dodecylsulphate (SDS), Triton X-100 (TX-100) and N -cetylpyridinium chloride (NCPC), together with the diazotizable substances aniline and sulphanilic acid and the coupling agents 1-naphthylamine and N -(1-naphthyl)ethylenediamine are used as model compounds. The protonation constants of the dyes follow the order SDS>H 2 O>TX-100>NCPC. In an SDS micellar solution the coupling rate increases greatly, allowing the rapid formation of the protonated dyes in an acetate buffer. Other advantages are the possibility of analysing very non-pola…
Electrically conductive hydrogel composites made of polyaniline nanoparticles and poly(N-vinyl-2-pyrrolidone)
2006
Abstract A novel electrically conductive composite material, consisting of polyaniline (PANI) nanoparticles dispersed in a polyvinyl pyrrolidone (PVP) hydrogel, was prepared ‘in situ’ by water dispersion polymerisation (DP) of aniline using PVP as steric stabiliser, followed by γ-irradiation induced crosslinking of the PVP component. Conversion yield of aniline into PANI particles was determined via HPLC and gas chromatography, while structural confirmation of the synthesised polymer was sought by FTIR. Morphology and dimensions of PANI particles into the coloured, optically transparent hydrogel was determined by electronic microscopy; moreover, swelling behaviour of composite hydrogels in …
Electrochemical and spectroscopic study on thiolation of polyaniline
2013
Abstract Polyaniline (PANI) is a conducting polymer, easily synthesized and lucrative for many electrochemical applications like ion-selective sensors and biosensors. Thiolated molecules, including biological ones, can be bound by nucleophilic attachment to the polyaniline backbone. These covalently bound thiols add functionality to PANI, but also cause changes in the electrochemical properties of PANI. Polyaniline studied in this work was electropolymerized on glassy carbon electrodes. 2-Mercaptoethanol (MCE) and 6-(ferrocenyl)hexanethiol (FCHT) were used as the thiols to form functionalized films. The films were characterized by cyclic voltammetry (CV), ex situ FTIR and Raman spectroscopi…
Comprehensive Study of Poly(2,3,5,6-tetrafluoroaniline): From Electrosynthesis to Heterojunctions and Ammonia Sensing.
2018
In this work, we report for the first time on a comprehensive study of poly(2,3,5,6-tetrafluoroaniline) (PTFANI). Contrary to the nonfluorinated polyaniline (PANI) or its analogues bearing one fluorine atom, PTFANI is a poorly conductive material. We present a comprehensive study of the electrosynthesized PTFANI from its monomer in an acidic aqueous medium. PTFANI was fully characterized by a potential-pH diagram, spectroelectrochemistry, and electrochemical quartz crystal microbalance (EQCM) measurements, as well as by a morphological study. Combined with the X-ray photoelectron spectroscopy (XPS) analysis, it allowed us to understand the redox properties of this polymer compared to those …
Solid-state electrochemistry of LDH-supported polyaniline hybrid inorganic–organic material
2008
Abstract The solid-state electrochemistry of a Zn–Al layered double hydroxide-supported polyaniline material (LDH-PANI) in contact with aqueous electrolytes is described. Interconversion processes between different forms (emeraldine, protoemeraldine, leucoemeraldine, nigraniline and pernigraniline) of the LDH-supported polyaniline units are involved in redox processes. This material exhibits significant variations of impedance upon application of different conditioning potentials, acting as an electrochemical frequency filter. Using Fe (CN) 6 4 - as redox probe, LDH-PANI can be used as a chemical–electrochemical information processing system equivalent to different combinational logic circu…