MNDO-PM3 Study of the Early Stages of the Chemical Oxidative Polymerization of Aniline

2006 ◽  
Vol 71 (10) ◽  
pp. 1407-1426 ◽  
Author(s):  
Gordana Ćirić-Marjanović ◽  
Miroslava Trchová ◽  
Jaroslav Stejskal
Keyword(s):  
Oxidative Polymerization ◽  
Heat Of Formation ◽  
Reaction Pathways ◽  
Chain Growth ◽  
Pani Chain ◽  
Initiation Phase ◽  
Aniline Oligomers ◽  
Semi Empirical ◽  
Quantum Chemical Computations ◽  
Aniline Polymerization

The theoretical approach to the study of aniline polymerization mechanism has been based on the MNDO-PM3 semi-empirical quantum chemical computations of the heat of formation of aniline dimer and trimer intermediates. The oxidation in aqueous medium without added acid is analyzed. The aniline nitrenium cation is proposed to be the reactive electrophilic species generated by the oxidation of aniline with a two-electron oxidant, ammonium peroxydisulfate, in the initiation phase. 4-Aminodiphenylamine and its fully oxidized form, N-phenyl-1,4-benzoquinonediimine, are the main dimeric products. 2-Aminodiphenylamine and its fully oxidized form, N-phenyl-1,2-benzoquinonediimine, are the most important side products of aniline dimerization. The influence of protonation on the oxidizability of aniline and reaction intermediates was studied. The dominant aniline oligomers have been shown to be linear as well as branched. The importance of reactivity difference between fully oxidized aniline oligomers composed of odd or even numbers of constitutional aniline units is pointed out. The species with odd numbers of aniline units, having nitrenium cationic nature, are much more reactive. The oxidation combined with intramolecular cyclization reaction pathways leads to substituted phenazines, characteristic of two-dimensional PANI chain-growth.

Fabrication of Conductive Textile via Chemical Oxidative Polymerization of Aniline on Polyester Cloth

2018 ◽  
Author(s):  
alireza razaghi
Keyword(s):  
Acidic Solution ◽  
Oxidative Polymerization ◽  
Morphological Structure ◽  
Infrared Spectrometry ◽  
Aniline Monomer ◽  
Polyester Textile ◽  
Conductive Polyaniline ◽  
Conductive Textile ◽  
Polymerization Conditions ◽  
Aniline Polymerization

In this research aniline polymerization conditions were optimized in presence of pre-treated polyester textile to achieve as high electrical conductivity as 100 S/Cm. Alkaline activation of the polyester textile was followed by immersion in to aqueous acidic solution of aniline monomer. Then the oxidant solution was used to initiate the polymerization. Finally, the prepared product was washed and dried prior to ant test. Functional groups were studied by Fourie-transformed infrared spectrometry (FTIR) from the surface of the polyaniline coated textile. Also, morphological structure of synthesized conductive polyaniline was studied by scanning electron microscopy (SEM). The synthesized cloth was used in a closed circuit in order to light up alight emitting diode to emphasis the conductivity of the textile and fibres that synthesised by this method.

Fabrication of Conductive Textile via Chemical Oxidative Polymerization of Aniline on Polyester Cloth

2018 ◽  
Author(s):  
alireza razaghi
Keyword(s):  
Acidic Solution ◽  
Oxidative Polymerization ◽  
Morphological Structure ◽  
Infrared Spectrometry ◽  
Aniline Monomer ◽  
Polyester Textile ◽  
Conductive Polyaniline ◽  
Conductive Textile ◽  
Polymerization Conditions ◽  
Aniline Polymerization

In this research aniline polymerization conditions were optimized in presence of pre-treated polyester textile to achieve as high electrical conductivity as 100 S/Cm. Alkaline activation of the polyester textile was followed by immersion in to aqueous acidic solution of aniline monomer. Then the oxidant solution was used to initiate the polymerization. Finally, the prepared product was washed and dried prior to ant test. Functional groups were studied by Fourie-transformed infrared spectrometry (FTIR) from the surface of the polyaniline coated textile. Also, morphological structure of synthesized conductive polyaniline was studied by scanning electron microscopy (SEM). The synthesized cloth was used in a closed circuit in order to light up alight emitting diode to emphasis the conductivity of the textile and fibres that synthesised by this method.

Oxidative Polymerization of 3-Amino,2'-,(3')–Nitrodiphenylazomethin

2018 ◽  
Vol 935 ◽  
pp. 134-139 ◽  
Author(s):  
Timur A. Borukaev ◽  
A.Kh. Malamatov ◽  
M.K. Vindizheva ◽  
A.V. Orlov ◽  
S.G. Kiseleva
Keyword(s):  
Thermal Stability ◽  
Thermal Properties ◽  
Chemical Structure ◽  
Oxidative Polymerization ◽  
Polymerization Process ◽  
Chain Growth ◽  
Polymer Product ◽  
Two Stages

Oxidative polymerization of 3-amino,2'-,(3')-nitrodiphenylazomethine was carried out in various ways. A possible mechanism for the polymerization of 3-amino,2'-,(3')- nitrodiphenylazomethine, where chain growth occurs as type N-C, is shown. It has been found that the yield of the polymer product is affected by the polymerization process and time. The chemical structure of the polymers obtained is established. The study of the thermal properties of polymers showed a low thermal stability and the process of destruction proceeds in two stages.

STRUCTURAL, ELECTRONIC AND QSAR PROPERTIES OF THE CYFLUTHRIN MOLECULE: A THEORETICAL AM1 AND PM3 TREATMENT

2006 ◽  
Vol 17 (10) ◽  
pp. 1391-1402 ◽  
Author(s):  
EMİNE DENİZ ÇALIŞIR ◽  
ŞAKİR ERKOÇ
Keyword(s):  
Energy Level ◽  
Gas Phase ◽  
Ground State ◽  
Heat Of Formation ◽  
Tobacco Budworm ◽  
Vibrational Modes ◽  
Lumo Energy ◽  
Deciduous Fruit ◽  
Semi Empirical ◽  
Homo Energy Level

Cyfluthrin is a synthetic cyano-containing pyrethroid insecticide that has both contact and stomach poison action. It is a nonsystemic chemical used to control cutworms, ants, silverfish, cockroaches, mosquitoes, tobacco budworm and many others. Its primary agricultural uses have been for control of chewing and sucking insects on crops such as cotton, turf, ornamentals, hops, cereal, corn, deciduous fruit, peanuts, potatoes, and other vegetables. Cyfluthrin is also used in public health situations and for structural pest control. The structural, vibrational, electronic and QSAR properties of the cyfluthrin molecule in gas phase have been investigated theoretically by performing molecular mechanics method by using MM+ force field, and semi-empirical molecular orbital AM1 and PM3 calculations. The geometry of the molecule has been optimized, infrared spectrum (vibrational modes and intensities) and the electronic properties of the molecule have been calculated in its ground state. According to PM3 calculation, heat of formation of cyfluthrin molecule is about -48.58 kcal/mol (exothermic), which shows that this molecule thermodynamically be stable. The HOMO energy level for this molecule is found to be -9.701 eV and the LUMO energy level is -0.660 eV giving rise to a gap of 9.041 eV, which also indicates that cyfluthrin is thermodynamically stable.

scholarly journals Thermodynamic investigation of promethazine, loratadine, cetirizine and buclizine as antihistamine drugs; monte carlo and semi-empirical studies

2020 ◽  
Vol 33 (01) ◽  
pp. 94-108
Author(s):  
Mina Zakeri ◽  
Majid Monajjemi ◽  
Ali Ebrahimi
Keyword(s):  
Total Energy ◽  
Frequency Analysis ◽  
Empirical Studies ◽  
Zero Point ◽  
Heat Of Formation ◽  
Electronic Energy ◽  
Basis Set ◽  
Amber Force Field ◽  
Environment Temperature ◽  
Semi Empirical

In this article, we discussed about four antihistamine drug called promethazine, loratadine, cetirizine and buclizine. Promethazine in this list is the only one in first generation antihistamine classification with CNS sedation effect and the other three belongs to second generation antihistamine group which are non-sedation and used to treat in many different anti-allergenic fields. In the following we optimized potential, kinetic and total energy of these molecules at body temperature (310 k˚) and environment temperature (298 k ˚) using Mont Carlo method in Amber force field in 500 ns. The quantum mechanics calculations and molecular structure of these molecules investigated using B3LYP level of theory with 6-31 G (d) as a basis set. Theoretical computations were performed to study thermodynamic parameters and frequency analysis. Electronic, thermal, zero point and gibs free energy and enthalpy were estimated in frequency analysis. Semi empirical computations were summarized to pm3 method and different energy parameters (total energy, Binding Energy, Isolated Atomic Energy, Electronic Energy, Core–Core Interaction and Heat of Formation.

Fabrication of Polyaniline on Silane-Functionalized Zinc Oxide

2018 ◽  
Vol 775 ◽  
pp. 94-98 ◽  
Author(s):  
James Christian M. Dizon ◽  
Alvin Karlo Garcia Tapia ◽  
Ivy Razado-Colambo ◽  
Marvin U. Herrera
Keyword(s):  
Zinc Oxide ◽  
Coupling Agent ◽  
Oxidative Polymerization ◽  
Ethanol Solution ◽  
Ftir Spectra ◽  
Polymeric Chain ◽  
Oxide Particles ◽  
Zinc Oxide Particles ◽  
Aniline Polymerization

In this study, polyaniline on silane-functionalized zinc oxide was fabricated. The zinc oxide particles were functionalized by soaking in silane aniline-ethanol solution. Afterwhich, the polyaniline was polymerized on the grafted silane aniline molecules using oxidative polymerization. The FTIR spectra showed vibrational peaks associated with the silane aniline molecules and grafted polyaniline. The sampled soaked in silane aniline coupling agent showed FTIR peaks associated with grafted silane aniline. The sample soaked for one minute showed FTIR peaks associated with ortho-coupled aniline units that is formed during the start of aniline polymerization. The sample soaked for three minutes showed FTIR peaks that is broader compared to others due to ring vibration in long polymeric chain.

scholarly journals Influence of Acidity and Oxidant Concentration on the Nanostructures and Electrochemical Performance of Polyaniline during Fast Microwave-Assisted Chemical Polymerization

Polymers ◽  
2020 ◽  
Vol 12 (2) ◽  
pp. 310 ◽  
Author(s):  
Biwei Qiu ◽  
Jingyun Wang ◽  
Zhoujing Li ◽  
Xia Wang ◽  
Xiaoyan Li
Keyword(s):  
Electrical Conductivity ◽  
Electrochemical Performance ◽  
Oxidative Polymerization ◽  
Molecular Structures ◽  
Chain Growth ◽  
Acidic Solutions ◽  
Microwave Assisted ◽  
Oxidant Concentration ◽  
Weakly Acidic Solution ◽  
Hcl Concentration

Polyaniline (PANI), a typical conducting polymer, has attracted great interest as an electrode material. A series of PANIs were prepared through fast microwave-assisted chemical oxidative polymerization with varying HCl and APS concentrations here. It was found that the microwave synthesized PANIs had ~4 times higher for the yields and 7~10 times higher for the electrical conductivity in comparison to PANI samples prepared using conventional method. PANI nanosheets could easily be fabricated in weakly acidic solution due to their oligomeric structure, which contained flat phenazine rings. By contrast, linear PANI chains produced in highly acidic solutions formed nanofibers. The APS concentration did not significantly affect the molecular structures of PANIs under the conditions here. However, increasing the concentration of APS produced nanofibers with shorter branches, which may be due to secondary nucleation during chain growth resulting from increases in active initiation centers. The electrical conductivity and electrochemical performance of PANIs were both improved with increasing HCl and APS concentrations. Improvements due to increases in HCl concentration may be attributed to additions in conjugation length and enrichment of doping levels, while improvements due to increases in APS concentration could be attributed to the increased crystallinity of PANI, which facilitates ion transport.

Self-organization of polyaniline during oxidative polymerization: formation of granular structure

2013 ◽  
Vol 67 (8) ◽  
Author(s):  
Mikhail Shishov ◽  
Vyacheslav Moshnikov ◽  
Irina Sapurina
Keyword(s):  
Polymer Chain ◽  
Oxidative Polymerization ◽  
Cation Radical ◽  
Spherical Particles ◽  
Self Organization ◽  
Chain Growth ◽  
Pani Film ◽  
Sphere Diameter ◽  
Diffusion Limited Aggregation ◽  
Polymer Chain Growth

AbstractThe paper is focused on oxidative polymerization of aniline proceeding in an acid medium with a strong oxidant; formation of polyaniline (PANI) granular structures in different steps of the synthesis was studied. The relationship between the processes of self-organization of the growing polymer into supramolecular structures and the steps of molecular synthesis has been revealed. It was shown that during the induction period (the initial synthesis step), insoluble non-conducting products are formed. They are characterized by the absorption band at 430 nm corresponding to the wavelength of the phenazinium cation radical peak. In the second step, the polymer chain growth, conducting PANI granules with the diameter of 50 nm were obtained. These granules consist of spherical particles with the diameter as small as several nanometers. Then, the granule dimensions increased to 200 nm due to the growth of the spheres; the sphere diameter reached 20 nm. The number of spheres in a granule remained constant. Both precipitate and PANI film consist of common structural elements, polymer spheres, organized into granules and larger structures. Suppression of the polymer chain growth leads to the formation of non-conducting aniline oligomers which are self-organized into large particles with fractal structure. To describe the self-organization processes of a growing polymer chain, the diffusion-limited aggregation mechanism was used.

scholarly journals Synthesis, Characterization and Thermal Studies of Cr (III), Co (II) and Ni (II) Complexes with Schiff Base

2020 ◽  
Vol 11 (4) ◽  
pp. 8026-8033
Author(s):  
Dina A. Najeeb ◽  
Farah M. Ibrahim
Keyword(s):  
Schiff Base ◽  
Transition Metal ◽  
Theoretical Calculations ◽  
Thermal Studies ◽  
Transition Metal Ions ◽  
Heat Of Formation ◽  
Hydroxyl Groups ◽  
Theoretical Treatment ◽  
Type Composition ◽  
Semi Empirical

The physiologically active compounds of Schiff bases find application in the treatment of several diseases. This biological activity of Schiff base is attributed to the formation of stable chelates with a transition metal, and they are known to exhibit a wide variety of pharmacological properties and carcinostatic activities. Cr (III), Co (II), and Ni (II) complexes of Schiff base were chosen for the present experimental work and theoretical treatment and characterized by different spectroscopies such as elemental analysis CHN, infrared, ultra visible spectroscopies, magnetic susceptibility, molar conductivity measurements, and thermal analysis The results of this research, indicate that the complexes have a type composition [M (NL)]. Schiff base NL: derived from 2-aminobenzoic acid and Benzil, M: Cr (III), Co (II), and Ni (II) transition metal ions. Schiff base acts as a tetradentate ligand with ions through the hydroxyl groups and imine groups. The work was included theoretical calculations of NL and its complexes, which were done by the program of hyperchem8. 0.7 using semi-empirical calculations. The PM3 method used to calculate the heat of formation (ΔH○f), binding energy (ΔEb), total energy (ΔEtot), and geometric properties of the compounds. 

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