The textile-wet process enormously consumes a large volume of water and chemicals, and thus awareness of cleaner production has been growing to protect the environment from the industrial effluents. In this context, reactive dyeing of... more
The textile-wet process enormously consumes a large volume of water and chemicals, and thus awareness of cleaner production has been growing to protect the environment from the industrial effluents. In this context, reactive dyeing of cellulosic materials such as cotton fabrics is a major sector of textile coloration that necessitates the use of a large amount of sodium sulfate or sodium chloride and alkali to exhaust and fix the dye molecules with cellulosic macromolecules, respectively. However, the remaining salt and alkali in the effluent badly affect the environment. For this purpose, the use of trisodium nitrilotriacetate (TNA) in reactive dyeing of cotton fabrics was hypothesized to have a double benefit, one as an exhausting agent (organic salt) and the second as a fixing agent (organic base). Thus, the exhaust dyeing characteristics of cotton fabrics using C.I. Reactive Yellow 145 (RY145) was optimized under different conditions of TNA concentration, alkali concentration, t...
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ABSTRACT
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A series of diand tri-substituted 1,3,5-triazine derivatives has been synthesized from the reaction of 2,4-dichloro-6-(trityloxy)-1,3,5-triazine with some cyclic secondary amines as morpholine, piperidine and piperazine in the presence of... more
A series of diand tri-substituted 1,3,5-triazine derivatives has been synthesized from the reaction of 2,4-dichloro-6-(trityloxy)-1,3,5-triazine with some cyclic secondary amines as morpholine, piperidine and piperazine in the presence of anhydrous potassium carbonate by nuclophilic substitution reaction. The reaction of 2,4-dichloro-6-(trityloxy)1,3,5-triazine with 2-aminothiazole, 2-aminobenzo-thiazole, hydrazine hydrate, were also studied. The structures of the new products were characterized by common analytical and spectroscopic methods. The antimicrobial activity of prepared compounds against gram positive bacteria Staphylococcus aureus and Candida albicans were investigated.
A set of azo dyes were prepared by diazotization of a series of electronically different substituted anilines and subsequent azo coupling of these diazonium salts with ethyl 4,5-dihydro-5-oxo-2-aryl(1H)pyrrole-3-carboxylate as a the... more
A set of azo dyes were prepared by diazotization of a series of electronically different substituted anilines and subsequent azo coupling of these diazonium salts with ethyl 4,5-dihydro-5-oxo-2-aryl(1H)pyrrole-3-carboxylate as a the coupling component. All of the dyes were confirmed as keto-hydrazone tautomers and were found as a mixtures of E- and Z- isomers with respect to the exocyclic C=N bond by 1H NMR spectroscopy. The absorption spectra are all similar irrespective of substituent and solvent. By comparison the fluorescence is strongly dependent on the electronic character of the substituents. All compounds fluoresce in a low temperature solvent glass and in the solid state except the ortho hydroxyl and ortho nitro derivatives and only the 4-cyanophenyl and 4-nitrophenyl derivatives show fluorescence in solution at room temperature. The spectroscopic behavior is explained in terms of competition between E/Z isomerisation and fluorescence after excitation. In the second part of...
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Smart clothes can be described as textiles that change their behavior under some external factors (stimulants). The response of the smart cloth can be passive (just as a sensor) or active (where a combination of sensing and another... more
Smart clothes can be described as textiles that change their behavior under some external factors (stimulants). The response of the smart cloth can be passive (just as a sensor) or active (where a combination of sensing and another reaction takes place). The materials involved in these textiles are crucial for many applications, especially for health related applications where the “wearables” can provide instantaneous monitoring and aid to people with certain disabilities. This work consists of two main parts: First it investigates the different materials used in smart clothing for monitoring the vital activities of the human body (e.g. the breathing rates) with an emphasis on piezoresistive structures as they work sensing elements for mechanical strains. Second this work presents the production of functional membrane samples based on synthesized pyrrolinone ester hydrazone dye with a preliminary investigation of their chemical and geometrical parameters, especially their sensitivit...
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Furopyrrolinone pigments were synthesized using solvent-free conditions and microwave heating. Soluble derivatives were prepared by N-butylation of pigment precursors. Absorption and fluorescence spectra were studied in DMSO both... more
Furopyrrolinone pigments were synthesized using solvent-free conditions and microwave heating. Soluble derivatives were prepared by N-butylation of pigment precursors. Absorption and fluorescence spectra were studied in DMSO both experimentally and theoretically, using time-dependent density functional theory. N-butylated derivatives show solid-state fluorescence.
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ABSTRACT The relation between structure and absorption of three symmetrical 2:1 octahedral Co(III) azo complexes was studied. Quantum chemical calculations based on density functional theory (DFT) relate well with E-azo configuration of... more
ABSTRACT The relation between structure and absorption of three symmetrical 2:1 octahedral Co(III) azo complexes was studied. Quantum chemical calculations based on density functional theory (DFT) relate well with E-azo configuration of ligands with coordinated nitrogen atoms coming solely from phenolic residues. DFT calculations estimate the mer stereoisomer as remarkably preferred with respect to any fac arrangement. Time dependent DFT calculations using B3LYP and CAM-B3LYP functionals were successfully used to interpret the absorption spectra in a visible range.
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ABSTRACT A series of six keto-hydrazone dyes was prepared by azo coupling of diazotised substituted 2-aminophenols with pyrrolinone esters. All keto- hydrazone compounds were found as a mixtures of E and Z isomers by 1H NMR. Irrespective... more
ABSTRACT A series of six keto-hydrazone dyes was prepared by azo coupling of diazotised substituted 2-aminophenols with pyrrolinone esters. All keto- hydrazone compounds were found as a mixtures of E and Z isomers by 1H NMR. Irrespective to the position of nitro substituent on the phenol ring, all compounds fluoresce strongly only in solvent glass at 77 K except 4-nitro derivatives which also weakly fluoresce in solution and in solid state at room temperature. Using these hydrazones as tridentate O–N–O´ ligands, six symmetrical 2:1 octahedral Co(III) complexes were prepared. Multinuclear NMR combined with 15N labelled hydrazone derivative proved that the starting mixture of hydrazone isomers was converted exclusively to E-azo configuration in complexes with coordinated nitrogen atoms coming solely from phenolic residues. The considerably different effect of 4- and 5-nitrophenol substituents on absorption spectra of the ligands and complexes was ascribed to prevailing azo character of an electronic structure of a ligand in the complex, based on TD DFT calculations.
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New disazo and polyazo ureido reactive dyes incorporating different reactive systems were synthesized and applied to cotton fabric by the exhaust dyeing method. Different factors affecting the dye ability and fastness properties of such... more
New disazo and polyazo ureido reactive dyes incorporating different reactive systems were synthesized and applied to cotton fabric by the exhaust dyeing method. Different factors affecting the dye ability and fastness properties of such dyes are investigated. Bis(monochlorotriazine) reactive dyes displayed higher primary exhaustion values compared to those obtained with bis(sulphatoethysulphone) and bis(monochlorotriazine/ sulphatoethysulphone) reactive dyes under different neutral exhaustion conditions. The results obtained indicate that the fixation efficiencies of these dyes were higher than those of dyes incorporating the bis(dichlorotriazine) reactive system. The results assessed for alkaline exhaust dyeing indicate that the bis(monochlorotriazine/sulphatoethylsulphone) dye was less sensitive to the variation in fixation temperatures than the other reactive dyes. The fastness properties of the ureido reactive dyes were fair to good. The improved dyeing performance of such type ...