Oxidative chemical polymerization kinetics of o-chloroaniline and characterization of the obtained polymer in aqueous hydrochloric acid solution using k2cr2o7 as oxidizing agent (original) (raw)
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Schiff base sal-2,5-Clan = 2-(2,5-dichlorobenzylideneamino)phenol was used as a new precursor for preparation of poly-2-(2,5-dichlorobenzylideneamino)phenol (PDCBAP). In anaqueous alkaline medium, NaOCl oxidant is capable of oxidative poly-condensation reaction (OP). Both sal-2,5-Clan and PDCBAP were characterized by solubility tests, FT-IR, 1 H-NMR spectroscopy and TG-DTA studies. FT-IR and 1 H-NMR spectrum of PDCBAP indicates the formation of Ar-OAr bond. According to TG/DTA curves, PDCBAP demonstrated higher resistance against temperature than sal-2,5-Clan. At optimum reaction conditions, viz. time = 14h, [NaOCl]0= 0.12 M, [KOH]0 = 0.1 M and T = 90°C, the yield of PDCBAP is52.17%. Thermal studies indicated that PDCBAP is more stable than sal-2,5-Clan.
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Poly(o-methoxyaniline) emeraldine-salt form (ES-POMA) was chemically synthesized using hydrochloric acid and subjected to a heat treatment (HT) process for 1 h at 100 °C (TT100) and 200 °C (TT200). The HT process promoted a progressive decrease in crystallinity. The Le Bail method revealed a decomposition from tetrameric to trimeric-folded chains after the HT process. The unheated POMA-ES presented a globular vesicular morphology with varied micrometric sizes. The heat treatment promoted a reduction in these globular structures, increasing the non-crystalline phase. The boundary length (S) and connectivity/Euler feature (χ) parameters were calculated from the SEM images, revealing that ES-POMA presented a wide distribution of heights. The TT100 and TT200 presented a narrow boundary distribution, suggesting smoother surfaces with smaller height variations. The UV-VIS analysis revealed that the transition at 343 nm (nonlocal π → π*) was more intense in the TT200 due to the electronic ...
2009
Department of Chemistry, Shivaji University, Kolhapur-415 004, Maharashtra, India <em>E-mail</em>: shitaLkakade09@yahoomllil.com <em>Manuscript received 27 December 2007, revised 21 August 2008, accepted 17 September 2008</em> The kinetics of oxidation of 4-chlorobenzyl alcohol with polymer supported chromic acid In 1 : 4 dioxane has been studied. The reaction is found to be zero order each in [alcohol] and [oxidant]. The effect of substituent on the rate of oxidation and the % of cross linking in polymeric resin (oxidant) are studied. Thermodynamic parameters are evaluated. The reaction product has been isolated and characterized by its derivative. A probable mechanism of oxidation is proposed.
Electrochimica Acta
In this work the electrochemical synthesis of polyanilne (PAni) in propylene carbonate (PC) medium in the presence of lithium perchlorate and di- (DCA) and tri-chloroacetic (TCA) acids was studied. In order to determine the best experimental conditions to grow an electroactive film of PAni by cyclic voltammetry, the effects of the supporting electrolyte and acid concentration were analysed. These experiments allowed us to conclude that although the degradation processes associated with the polymer are always present for both acids they are much stronger for DCA, probably due to its dimerization capability. In the presence of TCA a maximum ratio between polymer growth and polymer degradation was achieved. For aniline concentrations of 0.25 M and 0.5 M LiClO4, the electroactive PAni growth occurs only for acid concentrations higher than 1 M and 2 M, respectively for TCA and DCA. (C) 1997 Elsevier Science Ltd.
Chemistry Central journal, 2018
Electrically conductive polyorthochloroaniline/chromium nanocomposites (POC/Cr NCs) were prepared by in situ chemical oxidative polymerization of orthochloroaniline in the presence of Cr nanoparticles (Cr NPs). The load percentage of Cr nanofiller was varied in POC matrix to investigate the effect of Cr nanoparticles on the properties of the nanocomposites. The composition, structure, and morphology of POC and its composites were examined by Scanning electron microscopy, Fourier transform infrared spectroscopy, and UV-visible spectroscopic analysis. The antibacterial potential of POC and its composites was evaluated by the disc diffusion method against Escherichia coli and Bacillus subtilis. The results showed the improved antibacterial potential with the increase in the load percentage of nanofiller. The electrical conductivity of polymer and its composites was measured and correlated with the load percentage. The results showed that electrical conductivity of the composites was en...