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    Modification of carbohydrate polymers via grafting in Air. 2. Ceric-Initiated graft copolymerization of acrylonitrile onto natural and modified polysaccharides [electronic resource]

    , Article Starch - Stärke ; Volume 54, Issue 10, pages 482–488, October 2002 Pourjavad, A. (Ali) ; Zohuriaan-Mehr, Mohammad J
    Abstract
    Acrylonitrile (AN) was grafted onto various natural and modified polysaccharides (i.e., gum arabic, gum tragacanth, xanthan gum, sodium alginate, chitosan, sodium carboxymethyl cellulose, hydroxyethyl cellulose, methyl cellulose) by using ceric-carbohydrate redox initiating system. After overcoming practical problems, mainly from the high viscosity of the aqueous solutions of the different substrates, the graft copolymerization reactions were run either in air or in N2 atmosphere under similar conditions. Grafting was confirmed using chemical and spectral (FTIR) proofs. The reactions were kinetically investigated using semi-empirical expressions and time-temperature profiles. An anomalous... 

    Modification of carbohydrate polymers via grafting in air: 2. Ceric-initiated graft copolymerization of acrylonitrile onto natural and modified polysaccharides

    , Article Starch/Staerke ; Volume 54, Issue 10 , 2002 , Pages 482-488 ; 00389056 (ISSN) Pourjavadi, A ; Zohuriaan Mehr, M. J ; Sharif University of Technology
    2002
    Abstract
    Acrylonitrile (AN) was grafted onto various natural and modified polysaccharides (i.e., gum arabic, gum tragacanth, xanthan gum, sodium alginate, chitosan, sodium carboxymethyl cellulose, hydroxyethyl cellulose, methyl cellulose) by using ceric-carbohydrate redox initiating system. After overcoming practical problems, mainly from the high viscosity of the aqueous solutions of the different substrates, the graft copolymerization reactions were run either in air or in N2 atmosphere under similar conditions. Grafting was confirmed using chemical and spectral (FTIR) proofs. The reactions were kinetically investigated using semi-empirical expressions and time-temperature profiles. An anomalous... 

    Modified CMC. 4. Ceric-initiated methacrylonitrile graft polymerization onto carboxymethylcellulose

    , Article Journal of Polymer Materials ; Volume 21, Issue 4s , 2004 , Pages 351-359 ; 09738622 (ISSN) Pourjavadi, A ; Zohuriaan Mehr, M. J ; Pooraghaberar, A ; Hosseinzadeh, H ; Sharif University of Technology
    2004
    Abstract
    Graft copolymerization of methacrylonitrile (MAN) onto carboxymethylcellulose (CMC) was carried out under argon atmosphere in a homogeneous aqueous medium by using ceric ammonium nitrate (CAN) as an initiator. The FTIR spectroscopy and solubility characteristics of the products were used for confirming the graft copolymer formation. The effect of the concentration of the initiator, monomer and polysaccharide as well as the reaction time and temperature on the graft copolymerization reactions were investigated to achieve the optimum grafting conditions (i.e. CAN 0.00065 mol/L, MAN 0.85 mol/L, CMC 1% W/V, reaction temperature 45°C, and reaction time 2 h). According to the empirical rates of... 

    Modified chitosan. I. Optimized cerium ammonium nitrate-induced synthesis of chitosan-graft-polyacrylonitrile

    , Article Journal of Applied Polymer Science ; Volume 88, Issue 8 , 2003 , Pages 2048-2054 ; 00218995 (ISSN) Pourjavadi, A ; Mahdavinia, G. R ; Zohuriaan Mehr, M. J ; Omidian, H ; Sharif University of Technology
    2003
    Abstract
    Chitin was extracted from shrimp shells and then deacetylated to obtain chitosan. The degree of deacetylation of the chitosan was determined to be 0.76 using pH-metric titration. A large number of cyanide functional groups were introduced onto chitosan by grafting with polyacrylonitrile as an efficient way of modification. The graft copolymerization reactions were carried out under argon atmosphere in a homogeneous aqueous phase (containing a small portion of acetic acid) by using eerie ammonium nitrate as an initiator. Evidence of grafting was obtained by comparing FTIR spectra of chitosan and the graft copolymer as well as solubility characteristics of the products. The synthetic... 

    Michael-addition-initiated chemoselective three-component reaction for the synthesis of 2-(3-oxo-1,3-diarylpropyl)malononitrile derivatives using cerium(iv) ammonium nitrate in phosphorus ionic liquid

    , Article Polycyclic Aromatic Compounds ; 2021 ; 10406638 (ISSN) Bahrami, G. R ; Batooie, N ; Mousavi, R ; Miraghaee, S ; Hosseinzadeh, N ; Mousavian, M ; Hoshyari, A ; Sajadimajd, S ; Mohammadi, B ; Hatami, R ; Sharif University of Technology
    Taylor and Francis Ltd  2021
    Abstract
    The aim of this research is the study of hexyltriphenylphosphonium bromide (HTPB) ionic liquid as a bifunctional promoter (solvent and catalyst) in the presence of cerium(IV) ammonium nitrate as a single electron oxidant for the Michael reaction at room temperature and solvent-free conditions. A novel, one-pot and environmentally benign the process to achieve the chemoselective of 2-(3-oxo-1,3-diarylpropyl)malononitrile derivatives instead of 2-(1,3-diarylallylidene)malononitriles using a three-component reaction involving acetophenone derivatives, various aromatic aldehydes and malononitrile was developed. This protocol is simple and provides biologically interesting products in good... 

    Modified CMC: Part1-optimized synthesis of carboxymethyl cellulose-g-polyacrylonitrile

    , Article Iranian Polymer Journal (English Edition) ; Volume 14, Issue 2 , 2005 , Pages 131-138 ; 10261265 (ISSN) Zohuriaan Mehr, M. J ; Pourjavadi, A ; Sadeghi, M ; Sharif University of Technology
    2005
    Abstract
    As the first part of a continued research on conversion of carboxymethyl cellulose-sodium salt (CMC) to useful biopolymer-based materials, large numbers of cyanide functional groups were introduced onto CMC by grafting with polyacrylonitrile (PAN). The graft copolymerization reactions were carried out under nitrogen atmosphere using ceric ammonium nitrate (CAN) as an initiator. Evidence of grafting was obtained by comparing FTIR spectra of CMC and the graft copolymer as well as solubility characteristics of the products. The synthetic conditions were systematically optimized through studying the effective factors including temperature and concentrations of initiator, acrylonitrile monomer,... 

    Synthesis and characterization of bagasse poly(methyl methacrylate) graft copolymer

    , Article Macromolecular Symposia ; Volume 274, Issue 1 , 2008 , Pages 49-54 ; 10221360 (ISSN) Sarvi, I ; Pourjavadi, A ; Noei Aghaei, M. A ; Sharif University of Technology
    2008
    Abstract
    Graft copolymerization of methyl methacrylate (MMA) was carried out on bagasse fibers in an aqueous medium using eerie ammonium nitrate (CAN) as initiator under a neutral atmosphere. In order to obtain the optimum condition for graft copolymerization, the effects of initiator concentration, temperature, time of reaction, and monomer concentration were studied. The maximum grafting percent was found to be 122%. The bagasse grafted poly(methyl methacrylate) was characterized by FTIR and its thermal behavior was characterized by TGA. Copyright © 2008 WILEY-VCH Verlag GmbH & Co. KGaA  

    A very simple method to synthesize nano-sized manganese oxide: An efficient catalyst for water oxidation and epoxidation of olefins

    , Article Dalton Transactions ; Volume 41, Issue 36 , Jul , 2012 , Pages 11026-11031 ; 14779226 (ISSN) Najafpour, M. M ; Rahimi, F ; Amini, M ; Nayeri, S ; Bagherzadeh, M ; Sharif University of Technology
    RSC  2012
    Abstract
    Nano-sized particles of manganese oxides have been prepared by a very simple and cheap process using a decomposing aqueous solution of manganese nitrate at 100 °C. Scanning electron microscopy, transmission electron microscopy and X-ray diffraction spectrometry have been used to characterize the phase and the morphology of the manganese oxide. The nano-sized manganese oxide shows efficient catalytic activity toward water oxidation and the epoxidation of olefins in the presence of cerium(iv) ammonium nitrate and hydrogen peroxide, respectively  

    Heterogeneous water oxidation by bidentate schiff base manganese complexes in the presence of cerium(IV) ammonium nitrate

    , Article Transition Metal Chemistry ; Volume 34, Issue 4 , 2009 , Pages 367-372 ; 03404285 (ISSN) Najafpour, M. M ; Boghaei, D. M ; Sharif University of Technology
    2009
    Abstract
    Oxygen evolution was observed upon mixing solid manganese(III) bidentate Schiff base complexes with aqueous solutions of cerium(IV) ammonium nitrate. However, oxygen evolution was not observed upon mixing solutions of the complexes (in acetonitrile) with Ce(IV). Electron-withdrawing substituents on the Schiff base ligands (NO2, Br) enhanced the reactivity of the manganese complexes toward oxygen evolution. Oxygen evolution was also affected by R groups on the ligands, in the order Me > Et Bz. © 2009 Springer Science+Business Media B.V