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SYNTHESIS OF SOLUBLE POLY(3,4-DIHYDROXY-o-TOLYLENE):REDOX POLYMER

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Chinese Journal of Polymer Science 2006年第1期24卷 41-46页

作者： Sad Moulay Fatima M'zyène laboratoire de chimie-Physique moléculaire et Macromoléculaire Faculté des Sciences de l'Ingénieur Département de chimie Industrielle Université de BlidaRoute de SoumèaB.P.270Blida 09000Algeria. laboratoire de chimie-Physique moléculaire et Macromoléculaire Faculté des Sciences de l'Ingénieur Département de chimie Industrielle Université de BlidaRoute de SoumaB.P.270Blida 09000Algeria.

Conventional chloromethylation, paraformaldehyde/hydrogen chloride in acetic acid medium, was applied to 1,2- dimethoxybenzene. Chloroform-soluble poly（3,4-dimethoxy-o-tolylene） was obtained with an intrinsic viscosity of 0.034 dL g^-1. The polymer was evaluated as a condensation redox polymer precursor formed by a Friedel-Crafts reaction. Cleavage of the methoxy groups present in this polymer resulted in poly（3,4-dihydroxy-o-tolylene） which manifested a great air-oxidation resistance. The redox property of the latter polymer was found to be 1017 mV by potentiometric titration with 0.05 N ceric ammonium nitrate at 25℃. This midpotential was compared to that of catechol, a monomeric analogue, under the same titration conditions.

关键词： Poly(3,4-dimethoxy-o-tolylene) Poly(3,4-dihydroxy-o-tolylene) Redox polymer.

HALOMetHYLATION OF POLYSTYRENE AND SUBSEQUENT PYRIDINATION VIA A HOmolYTIC PATHWAY

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Chinese Journal of Polymer Science 2006年第6期24卷 627-635页

作者： Sad Moulay Nadia Mehdi laboratoire de chimie-Physique moléculaire et Macromoléculaire Faculté des Sciences de l'Ingénieur Departement de Chimie IndustrielleUniversité de BlidaRoute de SoumaB. P. 270Blida 09000Algeria

Chloromethylation of polystyrene （PS） with two different chloromethylating systems methylal/thionyl chloride and paraformaldehyde/trimethylchlorosilane was studied. Soluble chloromethylated polystyrene with a degree of substitution of 89% was obtained. The Conant-Finkelstein reaction on the chloromethylated PS afforded soluble iodomethylated polystyrene with a degree of substitution as high as 96%. The reaction conditions of Minisci were employed to radically pyridinate PS via its iodomethylated derivative. Polyelectrolytes were formed which could be converted to normal polymers by treatment with a 20% aqueous solution of NaOH.

关键词： Chloromethylated polystyrene Conditions of Minisci Iodomethylated polystyrene Pyridinated polystyrene.

PYRIDINATION OF POLY(VINYL CHLORIde) via A HOmolYTIC PATHWAY

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Chinese Journal of Polymer Science 2007年第3期25卷 297-302页

作者： Sad Moulay Zakia Zeffouni laboratoire de chimie-Physique moléculaire et Macromoléculaire Faculté des Sciences de l'Ingénieur Département de Chimie IndustrielleUniversité Sad Dahlab de BlidaRoute de SoumaB. P. 270Blida 09000Algeria

PVC was subjected to a chemical modification aiming at replacing the chlorine atoms by pyridine groups via a homolytic route. Pyridine groups were peculiarly affixed to the PVC matrix via a carbon-carbon bond rather than a carbonnitrogen one. PVC was first iodinated using the Conant-Finkelstein reaction, followed by the application of the homolytic conditions of Minisci to generate pyridinated PVC with a varying degree of substitution. The extent of substitution was not high; the reaction on 30% iodinated PVC afforded a degree of modification no greater than 3%.

关键词： Conditions of Minisci Iodinated PVC Pyridinated PVC

PHONONS IN POLYACENIC CHAINS

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Chinese Journal of Polymer Science 2006年第3期24卷 229-236页

作者： O.Rafil M.Tamine B.Bourahla R.Tigrine S.Amoudache A.Khater laboratoire de Physique et chimie Quantique laboratoire de Physique de l'etat Condensé

We have theoretically resolved phonon excitations in quasi-two-dimensional organic crystals of polyacenic semiconductor material which may be obtained by the pyrolytic treatment of phenol-formaldehyde resin. A model for studying the dynamical properties using three polyacene chains is proposed with the aim to present the vibrational properties of this structure. It employs the formalism of solid states in two dimensions which admit phonons. A simulation process of the two-dimensional lattice structure shows that elastic waves may explain the existence of vibrational modes in the frequency range 100-400 cm^-1. The presence of acoustic and optical like phonons is discussed in terms of the elastic force constants. A hyperfine resonance structure is obtained. It allows the analysis of the dynamical evolution in thin films of polyacene. It is found that the behavior of the phonon density of states exhibits resonance between modes in the structure.

关键词： Polymers Elastic waves Surface phonons Localized modes

Direct oxidation of methane to oxygenates over heteropolyanions

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Journal of Natural Gas Chemistry 2008年第3期17卷 309-312页

作者： Ouarda Benlounes Sadia Mansouri Chérifa Rabia Smain Hocine laboratoire de chimie Appliqueé et de Génie Chimique Université Mouloud Mammeri laboratoire de chimie du Gaz Naturel Institut de Chimie USTHB

Partial oxidation of methane to formaldehyde and methanol was studied at atmospheric pressure in the temperature range of 700-750 °C using heteropolycompound catalysts （NH4）6HSiMo11FeO40, （NH4）4PMo11FeO39, and H4PMo11VO40, which were prepared and characterized by various analysis techniques such as infrared, visible UV, XRD and DTA. O2 or N2O was used as the oxidizing agent, and the principal products of the reaction were CH3OH, CH2O, CO, CO2, and water. The conversion and the selectivity of products depend strongly on the reaction temperature, the nature of oxidizing agent, and the composition of catalyst.

关键词： methane oxidation heteropolycompounds methanol oxygenates

Ab initio simulation of the sum-frequency generation response of optically active liquids in the presence of a dc electric field —determination of the absolute molecular configuration

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Science China Chemistry 2014年第10期57卷 1405-1408页

作者： CHAMPAGNE Benot QUINet Olivier laboratoire de chimie Théorique Unité de Chimie Physique Théorique et Structurale Université de Namur

Quantum chemical computations have been performed to evaluate the first and second hyperpolarizability quantities of the interference term, linear in the external static electric field, that appear in the electric field-induced sum-frequency generation signal of chiral liquids. These are performed at the time-dependent Hartree-Fock level on the prototypical 1,1′-bi-2-naphtol chiral species.

关键词： second and third hyperpolarizabilities chirality nonlinear optics time-dependent Hartree-Fock

Electronic and Optical Properties of TiS2 determined from Generalized Gradient Approximation Study

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Chinese Physics Letters 2015年第9期32卷 96-99页

作者： Hamza El-Kouch Larbi El Farh Jamal Sayah Allal Challioui laboratoire de mecanique & energetique Departement de Physique Faculte des Sciences Universite Mohmnmed Premier Oujda Maroc laboratoire de chimie organique macromol~culaire et produits naturels Equipe: Photochimie et Chimie Macromoleculaire Faculte des Sciences Universite Mohammed Premier Oujda. Maroc

The electronic and optical properties of TiS2 are studied of density functional theory. A linearized and augmented by using an ab-initio calculation within the frame plane wave basis set with the generalized gradient approximation as proposed by Perdew et al. is used for the energy exchange-correlation determination. The results show a metallic character of TiS2, and the plots of total and partial densities of states of TiS2 show the metallic character of the bonds and a strong hybridization between the states d of Ti and p of S below the Fermi energy. The optical properties of the material such as real and imaginary parts of dielectric constant （ε（w） = ε1（w）＋ iε2（w））, refractive index n（w）, optical reflectivity R（w）, for E / /x and E / /z are performed for the energy range of 0-.14 eV.

关键词： Ti ab Electronic and Optical Properties of TiS2 determined from Generalized Gradient Approximation Study

Investigation of structural parameters and self-aggregation of Algerian asphaltenes in organic solvents

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Petroleum Science 2015年第3期12卷 509-517页

作者： Asma Larbi Mortada Daaou Abassia Faraoun laboratoire de Synthèse organique Physico-chimieBiomolcules et Environnement (LSPBE)Department of Industrial Organic ChemistryFaculty of ChemistryUniversity of Sciences and Technology of Oran laboratoire de chimie Physique Macromoléculaire (LCPM) Department of ChemistryFaculty of SciencesUniversity of Oran

Elemental analysis, Fourier transform infrared （FTIR）, 1H-NMR, fluorescence spectroscopy, and surface tension methods have been used to characterize the molecular structure and the aggregation behaviors of two asphaltenic fractions derived, respectively, from an Alge- rian petroleum well and a corresponding storage tank deposit. Elemental analysis, FTIR, ~H-NMR, and fluores- cence spectroscopy were used to investigate the chemical composition and structural parameters of asphaltenes, while the surface tension method was used to measure the critical micelle concentration （CMC） in organic solvents with different solubility parameters and polarities in order to characterize the asphaltenes＇ aggregation behaviors. Results show that the unstable asphaltenes fraction extracted from the storage tank deposit possesses a higher polarity （higher heteroatoms content） and a lower aro- maticity than stable asphaltenes from the petroleum well. The CMC results indicate that asphaltenes with high polarity and low aromaticity have a high solubility in polar solvents such as nitrobenzene, whereas asphaltenes with low polarity and high aromaticity are more soluble in solvents with weak polarity, like toluene. It is concludedthat the difference of structure of asphaltene samples and polarity of solvents can lead to difference of aggregation behaviors.

关键词： Asphaltenes Algerian petroleum Structural parameters - CMC

Synthesis, Structural Study and Phase Transitions Characterization by Thermal Analysis and Vibrational Spectroscopy of an Ammonium Rubidium Arsenate Tellurate

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Chemical Research in Chinese Universities 2016年第6期32卷 902-911页

作者： GHORBEL Khouloud LITAIEM Hajer KTARI Lilia GARCIA-GRANDA Santiago DAMMAK Mohamed laboratoire de chimie Inorganique(LCI) Universitd de Sfax Facultd des Sciences de Sfax BP 1171 Sfax 3000 Tunisia laboratoire de chimie Physique et Analytique Faeulte de Chimie Universitte d 'Oviedo Oviedo 33006 Espagne

The Rb2.42（NH4）0.58（HAsO4）（H2AsO4）. Te（OH）6 crystals（denoted by RbNAsTe） crystallize in the monoc-linic system, space group P21/n with the following parameters： a=1.3059（5） nm, b=0.6755（3） nm, c=1.6675（6） rim,β=94.126（4）°, Z=4 and V=1.46733（10） nm^3. Thermal analyses（DSC, DTA and TG） confirm the presence of the phasetransition and the temperatttre of the decomposition. The vibrational spectroscopy study at room temperature showthe presence and the independence of anionic groups, cationic groups, and give more importance to the hydrogenbonds. Raman spectra were recorded in the temperature range of 298--503 K. The temperature dependence of theRaman line shift, intensity reduction and the half width detects the phase transitions and confirms their nature. So, thephase transition at 453 K corresponds to the superprotonic-ionic conduction phase transition, and those at 483 and491 K correspond to the decomposition of our material.

关键词： RbNAsTe X-Ray diffraction Differential scanning calorimetry Phase transition Raman spectrometry