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oxidative-polymerization
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Synthesis, characterization, and catalysis of recyclable new piperazine-bridged Mo(VI) polymers [MoO 2(Salen)(piperazine)] n in highly selective oxygenation of alkenes and sulfides
, Article Journal of Coordination Chemistry ; Volume 66, Issue 16 , 2013 , Pages 2885-2900 ; 00958972 (ISSN) ; Zare, M ; Sharif University of Technology
2013
Abstract
This study reports synthesis and characterization of polymeric [MoO2(Salen)] complexes that combine MoO2(acac)2 and polymeric ligands bearing N2O2 coordination sites, abbreviated herein as [piperazinCH2{MoO2(Salen)}]n (6), [piperazinCH2{MoO2(Salophen)}]n (7), and [piperazinCH2{MoO2(Salpn)}]n (8). The epoxidation of alkenes using tert-butyl hydroperoxide and oxidation of sulfides to sulfoxides by urea hydrogen peroxide were enhanced with excellent selectivity under the catalytic influence of these coordination polymers. No relevant difference in activity was found due to change in the diamine in the Schiffs base ligands. The stability of polymeric catalysts was assessed by recycling a sample...
Highly conductive self-electrical stimuli core-shell conduit based on PVDF-chitosan–gelatin filled with in-situ gellan gum as a possible candidate for nerve regeneration: a rheological, electrical, and structural study
, Article Applied Nanoscience (Switzerland) ; Volume 11, Issue 8 , 2021 , Pages 2199-2213 ; 21905509 (ISSN) ; Ramazani Saadatabadi, A ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2021
Abstract
In the context of peripheral nerve injuries treatment, self-electrical stimuli nerve guidance conduit is a promising technique. To fabricate such structures, PVDF-chitosan–gelatin was considered for the outside walls of conduit and gellan gum containing conductive polyaniline-graphene (PAG) nanocomposite particles in the middle. PVDF-chitosan–gelatin nanofibers were prepared using the dual-electrospinning method and highly conductive binary-doped polyaniline-graphene was synthesized by chemical oxidative polymerization in the presence of aniline and sodium dodecyl sulfate. The morphology and chemical structure of nanofibers and PAG were characterized using SEM and FTIR analyses. The...
Conductive polymer-based microextraction methods: A review
, Article Analytica Chimica Acta ; Volume 767, Issue 1 , March , 2013 , Pages 1-13 ; 00032670 (ISSN) ; Ayazi, Z ; Naderi, M ; Sharif University of Technology
2013
Abstract
Conductive polymers (CPs) are classified as materials which exhibit highly reversible redox behavior and the unusual combined properties of metal and plastics. CPs, due to their multifunctionality, ease of synthesis and their stability, have attracted more attentions in different fields of research, including sample preparation. CPs along with several commercial hydrophilic sorbents, are alternative to the commercially available hydrophobic sorbents which despite their high specific surface areas, have poor interactions and retentions in the extraction of polar compounds. This review covers a general overview regarding the recent progress and new applications of CPs toward their synthesis...
Polymeric ionic liquid nanogel-anchored tungstate anions: A robust catalytic system for oxidation of sulfides to sulfoxides
, Article New Journal of Chemistry ; Volume 39, Issue 2 , 2015 , Pages 1348-1354 ; 11440546 (ISSN) ; Nazari Chamazkoti, M ; Hosseini, S. H ; Sharif University of Technology
Abstract
A new heterogeneous catalytic system was prepared by immobilization of tungstate ions on a cross-linked poly(ionic liquid) nanogel. The solid nanogel was easily synthesized by a surfactant-less method. The resulting catalyst was highly active in selective oxidation of sulfides to sulfoxides by H2O2. The oxidation reactions were successfully performed under solvent-free conditions affording high yields. The catalyst was recycled and reused for several reaction cycles without any significant loss of catalytic activity
Morphology transition control of polyaniline from nanotubes to nanospheres in a soft template method
, Article Polymer International ; Volume 64, Issue 1 , June , 2015 , Pages 88-95 ; 09598103 (ISSN) ; Ghorbani, M ; Shojaei, A ; Sharif University of Technology
John Wiley and Sons Ltd
2015
Abstract
A soft template route is reported for the fabrication of polyaniline nanospheres via the oxidative polymerization of aniline in the presence of β-naphthalenesulfonic acid (β-NSA) as both surfactqant and dopant, and ammonium persulfate as oxidant at 2-5°C. Control over the morphology and size of the nanoparticles was achieved by changing the reaction medium via addition of an organic cosolvent (i.e. ethanol or ethylene glycol) and by controlling the concentrations of aniline and β-NSA and the molar ratio of β-NSA to aniline. By this means the size of the β-NSA-aniline micelles and the way that aniline monomer interacts with the micelles were controlled. In fact the lower dielectric constant...
Synthesis of new 2-aryl-4-chloro-3-hydroxy-1H-indole-5,7-dicarbaldehydes via Vilsmeier-Haack reaction
, Article Journal of Heterocyclic Chemistry ; Volume 47, Issue 2 , 2010 , Pages 463-467 ; 0022152X (ISSN) ; Zirak, M ; Akbari, A ; Hashemi, M. M ; Sharif University of Technology
2010
Abstract
(Chemical Equation Presented) New 2-aryl-4-chloro-3-hydroxy-1H-indole-5,7- dicarbaldehydes were synthesized in three steps from acetophenone derivatives. By oxidation of acetophenones to aryl glyoxals using selenium dioxide and condensation with acetylacetone in the presence of ammonium acetate in water 3-acetyl-5-aryl-4-hydroxy-2-methyl-1H-pyrrols were obtained. 2-Aryl-4-chloro-3-hydroxy-1H-indole-5,7-dicarbaldehydes were synthesized via Vilsmeier-Haack reaction of pyrrole derivatives in moderate yields
The effect of titanium dioxide (TiO2) nanoparticles on hydroxyapatite (HA)/TiO2 composite coating fabricated by electrophoretic deposition (EPD)
, Article Journal of Materials Engineering and Performance ; Volume 27, Issue 5 , May , 2018 , Pages 2338-2344 ; 10599495 (ISSN) ; Afshar, A ; Salehi, S ; Sharif University of Technology
Springer New York LLC
2018
Abstract
Composite coatings of Hydroxyapatite (HA) with ceramics, polymers and metals are used to modify the surface structure of implants. In this research, HA/TiO2 composite coating was fabricated by electrophoretic deposition (EPD) on 316 stainless steel substrate. HA/TiO2 composite coatings with 5, 10 and 20 wt.% of TiO2, deposited at 40 V and 90 s as an optimum condition. The samples coated at this condition led to an adherent, continuous and crack-free coating. The influence of TiO2 content was studied by performing different characterization methods such as scanning electron microscopy (SEM), energy dispersive x-ray spectroscopy (EDS), corrosion resistance in simulated body fluid (SBF),...
HRP-dendron nanoparticles: The efficient biocatalyst for enzymatic polymerization of poly(2,5-dimethoxyaniline)
, Article Journal of Molecular Catalysis B: Enzymatic ; Volume 90 , June , 2013 , Pages 139-143 ; 13811177 (ISSN) ; Vossoughi, M ; Shahrokhian, S ; Alemzadeh, I ; Sharif University of Technology
2013
Abstract
Synthesis of poly(2,5-dimethoxyanilie) (PDMA) catalyzed by nano reengineered horseradish peroxidase (HRP) with dendritic macromolecules, was studied as a function of reaction media. UV-vis, gel permeation chromatography and conductivity measurements were used to explain how the reaction media compositions influence the physical properties of PDMA. Nanostructured PDMA was also synthesized by oxidative polymerization in a novel and green bi-catalyst system involving HRP and ferric chloride. FTIR and UV-vis analysis confirmed the formation of emeraldine salt state of PDMA. The thermal stability of reengineered HRP granted further studies on the polymerization using bi-catalyst system at...
A polythiophene–silver nanocomposite for headspace needle trap extraction
, Article Journal of Chromatography A ; Volume 1460 , 2016 , Pages 1-8 ; 00219673 (ISSN) ; Banihashemi, S ; Jelvani, S ; Sharif University of Technology
Elsevier B. V
Abstract
A nanocomposite consisting of polythiophene–silver was prepared and implemented as a desired sorbent for headspace needle trap extraction. Colloidal silver nanoparticles (Ag NPs) with narrow size distribution and high stability were synthesized in water–in–oil microemulsion. This simple procedure was adapted to prepare highly monodispersed Ag NPs, starting from an initial synthesis in sodium bis(2-ethylhexyl) sulfosuccinate (AOT) reverse micelles. Polythiophene (PT) was synthesized by chemical oxidative polymerization in the presence of anhydrous ferric chloride while its polymeric structure was confirmed by Fourier transform infrared spectrometry (FTIR). Eventually, the prepared PT was...
A novel magnetic poly(aniline-naphthylamine)-based nanocomposite for micro solid phase extraction of rhodamine B
, Article Analytica Chimica Acta ; Volume 794 , 2013 , Pages 38-46 ; 00032670 (ISSN) ; Daliri, R ; Roostaie, A ; Sharif University of Technology
2013
Abstract
A novel Fe3O4-poly(aniline-naphthylamine)-based nanocomposite was synthesized by chemical oxidative polymerization process as a magnetic sorbent for micro solid phase extraction. The scanning electron microscopy images of the synthesized nanocomposite revealed that the copolymer posses a porous structure with diameters less than 50nm. The extraction efficiency of this sorbent was examined by isolation of rhodamine B, a mutagenic and carcinogenic dye, from aquatic media in dispersion mode. Among different synthesized polymers, Fe3O4/poly(aniline-naphthylamine) nanocomposite showed a prominent efficiency. Parameters including the desorption solvent, amount of sorbent, desorption time, sample...
Molecularly imprinted polydopamine nano-layer on the pore surface of porous particles for protein capture in HPLC column
, Article Journal of Colloid and Interface Science ; Volume 404 , 2013 , Pages 117-126 ; 00219797 (ISSN) ; Shojaei, A ; Abdekhodaie, M. J ; Sellergren, B ; Sharif University of Technology
2013
Abstract
Bio-inspired Human Serum Albumin (HSA) imprinted polydopamine nano-layer was produced through oxidative polymerization of dopamine on the pore surface of HSA modified porous silica particles. The coating thickness was controlled by the reaction time and thereby varied within 0-12. nm. The samples were characterized by elemental analysis, FT-IR, DSC, SEM, TEM, TGA, physisorption and thermoporometry. The characterization confirmed the success of evolution and deposition of polydopamine layer on the silica pore surface. Batch rebinding experiment showed that the molecularly imprinted polymer (MIP) with 8.7. nm coating thickness, in comparison with the thinner and thicker coatings, displays the...
A novel needle trap sorbent based on carbon nanotube-sol-gel for microextraction of polycyclic aromatic hydrocarbons from aquatic media
, Article Analytica Chimica Acta ; Volume 683, Issue 2 , January , 2011 , Pages 212-220 ; 00032670 (ISSN) ; Ayazi, Z ; Aghakhani, A ; Sharif University of Technology
2011
Abstract
A new type of composite material based on carbon nanotubes (CNTs) and sol-gel chemistry was prepared and used as sorbent for needle trap device (NTD). The synthesized composite was prepared in a way to disperse CNTs molecules in a sol-gel polymeric network. CNT/silica composites with different CNT doping levels were successfully prepared, and the extraction capability of each composite was evaluated. Effects of surfactant and the oxidation duration of CNTs on the extraction efficiency of synthesized composites were also investigated. The applicability of the synthesized sorbent was examined by developing a method based on needle trap extraction (NTE) and gas chromatography mass spectrometry...