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Article
Publication date: 2 January 2018

Ayssar Nahle, Fadoua El-Hajjaji, Abdeslam Ghazoui, Nour-Eddine Benchat, Mustapha Taleb, Rafik Saddik, Abdelmalik Elaatiaoui, Mohammed Koudad and Belkheir Hammouti

The purpose of this paper is to study the inhibition effect of (6-phenyl-3-oxopyridazin-2-yl) acetohydrazide (GP4) on the corrosion of mild steel in acidic medium by…

Abstract

Purpose

The purpose of this paper is to study the inhibition effect of (6-phenyl-3-oxopyridazin-2-yl) acetohydrazide (GP4) on the corrosion of mild steel in acidic medium by gravimetric measurements, potentiodynamic polarization, and electrochemical impedance spectroscopy (EIS).

Design/methodology/approach

Weight loss measurements, potentiodynamic tests and EIS were performed during this study.

Findings

(6-phenyl-3-oxopyridazin-2-yl) acetohydrazide (GP4) was found to be a very efficient inhibitor for mild steel in 1.0 M HCl solution, reaching about 85 per cent with inhibitor concentration 1.0 × 10-3 M at 303 K.

Practical implications

(6-phenyl-3-oxopyridazin-2-yl) acetohydrazide (GP4) was found to play an important role in the corrosion inhibition of mild steel in acidic solution.

Originality/value

This paper is intended to be added to the family of pyridazine derivatives which are highly efficient inhibitors and can be used in the area of corrosion prevention and control.

Details

Anti-Corrosion Methods and Materials, vol. 65 no. 1
Type: Research Article
ISSN: 0003-5599

Keywords

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Article
Publication date: 10 July 2007

E.M.A. Yakout and S.H. El‐Sabbagh

Evaluation of uracil and/or benzothiazol derivatives as antioxidants in natural rubber mixes.

Abstract

Purpose

Evaluation of uracil and/or benzothiazol derivatives as antioxidants in natural rubber mixes.

Design/methodology/approach

Cyanoacetylurea 1, as a precursor, was prepared at a good yield from widely available, low‐cost chemicals. Compound 1 was treated with triethylorthoformate and amine derivatives in one pot reaction affording the target uracil derivative 3. Replacement of the cyano group in 1 by benzothiazol led to obtaining the interesting N‐hydroxy uracils containing benzothiazole moiety 5 at a good yield. Some of the compounds prepared was selected and were evaluated as antioxidants in natural rubber mixes. The rheometric characteristic of the compounded rubber and the physico‐mechanical properties of the vulcanizates were determined.

Findings

The cure rate index, tensile strength and modulus increased while the equilibrium swelling decreased, i.e. compound 5 behaved as a secondary accelerator. The rubber vulcanizates were subjected to thermal oxidative ageing at 90°C for up to seven days. It has been found that uracil and/or benzothiazol derivatives can protect natural rubber vulcanizates against oxidative deterioration.

Research limitations/implications

The compounds prepareds were difficult to dissolve, they needed solvents with high boiling points, e.g. DMF, DMSO to be dissolved and even then they are not completely dissolved.

Practical implications

Uracil and or benzothiazol derivatives have many industrial applications.

Originality/value

The new compounds were prepared from very cheap and widely available chemicals. The compounds synthesised showed good antioxidant behaviour in comparison with the commercial antioxidant (phenyl‐β‐naphthyl amine) industrially used.

Details

Pigment & Resin Technology, vol. 36 no. 4
Type: Research Article
ISSN: 0369-9420

Keywords

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Article
Publication date: 13 November 2007

M. Benabdellah, R. Souane, N. Cheriaa, R. Abidi, B. Hammouti and J. Vicens

To evaluate the effect of synthesised calixarenes as new inhibitors on the corrosion of steel in HCl media at various temperatures.

Abstract

Purpose

To evaluate the effect of synthesised calixarenes as new inhibitors on the corrosion of steel in HCl media at various temperatures.

Design/methodology/approach

Calixarenes have been synthesised and tested as corrosion inhibitors. Gravimetric technique and potentiodynamic polarisation and impedance spectroscopy methods were used.

Findings

Calixarenes exhibited a good inhibition. Their efficiency decreases slightly with temperature.

Research limitations/implications

It was found that the inhibition efficiency increases with the concentration of inhibitors to reach 92 per cent at 10−4M.

Practical implications

The efficiency of calixarene derivatives increases with the concentration and falls slowly with temperature to attain 84 per cent at 353 K range. Calixarenes can be used in chemical cleaning and pickling processes.

Originality/value

The originality of this work is to find an inhibitor to give protection close to 100 per cent.

Details

Pigment & Resin Technology, vol. 36 no. 6
Type: Research Article
ISSN: 0369-9420

Keywords

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Article
Publication date: 6 November 2017

Abdel-Zaher A. Elassar, Saleh M. Al-Mousawi, Maher Helmi Helal and Mohamed E. Elgazzar

The purpose of this paper is to prepare new disperse dyes and apply for dying polyester fabrics.

Abstract

Purpose

The purpose of this paper is to prepare new disperse dyes and apply for dying polyester fabrics.

Design/methodology/approach

The synthetic reaction was carried out through two steps: preparation of arylhydrazones and alkylation using enaminone and dimethylaminovinyl-pyridazine. The high temperature method was used to apply these dyes to polyester fibres.

Findings

The study revealed that there is a significant effect of the new prepared disperse dyes on polyester fabrics. The structures of the prepared dyes were established based on elemental analysis and spectral data (infra red (IR), mass spectrometry (MS) and proton nuclear magnetic resonance (1H-NMR), carbon 13th nuclear magnetic resonance (13C-NMR)).

Research limitations/implications

Disperse dyes containing heterocyclic moiety have attracted great academic and industrial attention owing to their significant. The potential of using disperse dyes easily prepared from arylhydrazones are promise broad applications for these dyes.

Practical implications

The presence of N-thienyl and N-pyridazinyl in the structure of the synthesised disperse dyes would be expected to add the bioactivity advantage. Also, it can be used in formulating the antimicrobial fabrics.

Social implications

The N-thienyl and N-pyrdiazinyl derivatives of azo dyes are expected to be superior to in the application for fabrics. It may be useful for other applications like painting.

Originality/value

This paper helps to synthesise novel thiophene or pyridazine-based dyestuff for application in dying properties on polyester fabric and study their fastness properties.

Details

Pigment & Resin Technology, vol. 46 no. 6
Type: Research Article
ISSN: 0369-9420

Keywords

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Article
Publication date: 1 August 2003

E.A.M. Youssef, D.E. El‐Nashaar and M.A. Abd El‐Ghaffar

Itaconic acid was reacted with phenylene diamine (ortho, meta and para) and o‐tolidine in boiling dekalin, using Dean and Stark apparatus. The polymers prepared were…

Abstract

Itaconic acid was reacted with phenylene diamine (ortho, meta and para) and o‐tolidine in boiling dekalin, using Dean and Stark apparatus. The polymers prepared were evaluated for their suitability as antioxidants for natural rubber vulcanizates. The amide polymers prepared showed high efficiency as antioxidants for rubber vulcanizates, exceeding the performance of commercial antioxidants. In addition, the results obtained are encouraging and support the use of these polymers from both the environmental and economical points of view.

Details

Pigment & Resin Technology, vol. 32 no. 4
Type: Research Article
ISSN: 0369-9420

Keywords

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Article
Publication date: 2 January 2018

Kumar P.E., Govindaraju M. and Sivakumar V.

The purpose of this paper is to study the corrosion inhibition performance of an eco-friendly drug clozapine on the corrosion of copper in 1.0 M nitric acid and 0.5 M…

Abstract

Purpose

The purpose of this paper is to study the corrosion inhibition performance of an eco-friendly drug clozapine on the corrosion of copper in 1.0 M nitric acid and 0.5 M sulfuric acid solutions.

Design/methodology/approach

The corrosion inhibition nature of inhibitor molecule was evaluated by weight loss, electrochemical impedance spectroscopy and potentiodynamic polarization studies. An attempt was made to correlate the molecular properties of neutral and protonated forms of inhibitor molecule using quantum chemical calculations. The effect of temperature on the corrosion inhibition efficiency was also studied using electrochemical impedance spectroscopy. The potential of zero charge was determined to explain the mechanism of corrosion inhibition.

Findings

The studies on corrosion inhibition performance of clozapine showed that it has good corrosion inhibition efficiency on the corrosion of copper in 1.0 M nitric acid and 0.5 M sulfuric acid solutions. The adsorption of clozapine molecules onto the copper surface obeyed the Langmuir adsorption isotherm. The value of free energy of adsorption calculated is very close to −40 kJmol−1, indicating that the adsorption is through electrostatic coulombic attraction and chemisorption. The decrease in the value of energy of activation with the addition of inhibitor also shows the chemisorption of the inhibitor on the metal surface. The potential of zero charge and quantum chemical studies confirmed that the protonated molecules also get involved in the corrosion inhibition process through physisorption.

Originality/value

The present work indicates that clozapine can act as a good corrosion inhibitor for the corrosion of copper in acid media.

Details

Anti-Corrosion Methods and Materials, vol. 65 no. 1
Type: Research Article
ISSN: 0003-5599

Keywords

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Article
Publication date: 25 October 2018

Amira E.M. Abdallah and Rafat M. Mohareb

This work aims to synthesize a series of novel acyclic and/or heterocyclic systems, as precursors for dyes with potential antimicrobial activity that could be used for…

Abstract

Purpose

This work aims to synthesize a series of novel acyclic and/or heterocyclic systems, as precursors for dyes with potential antimicrobial activity that could be used for simultaneous dyeing and antimicrobial textile finishing. Thus, a series of novel pyridine, thiophene and pyrazolo[3,4-b]pyridine derivatives were synthesized, and their antimicrobial and textile finishing properties were studied and evaluated.

Design/methodology/approach

The synthesis, structure elucidation and antimicrobial activities of the newly synthesized compounds based on 4,4-dicyano-3-phenyl-but-3-enoic acid phenylamide (1) were demonstrated. The minimal inhibitory concentration in μg/mL of the compounds showed significant antimicrobial activity against most of the tested organisms. On the other hand, their spectral characteristics and fastness properties were measured and evaluated. Antimicrobial activities of the dyed fabrics in terms of inhibition zones (mm) were measured and evaluated.

Findings

A series of novel heterocyclic compounds (Schemes 1-3) were synthesized based on starting material (1). Compounds (1), 2, 4a, 8a and 9c exhibited comparable or even higher antibacterial activities than the selected standards (ampicillin), while compounds 2, 3c, 3d, 4a and 8b revealed higher antifungal activities than the selected standard (cycloheximide). On the other hand, some dyes showed high antimicrobial evaluation on the dyed fabrics (nylon 66, acetate and polyester) expressed as size (mm) of inhibition zones (Tables I-IV).

Practical implications

Results revealed that many hydrazo and azo derivatives were synthesized from some pyridines and thiophenes. The antimicrobial evaluation and textile finishing of the newly synthesized products revealed significant and potent values of antimicrobial activity.

Originality/value

All the synthesized compounds were novel and most of them exhibited higher antimicrobial activities than the selected standards antibiotics, thus are valuable for simultaneous dyeing and antimicrobial functional finishing of textile fabrics.

Details

Pigment & Resin Technology, vol. 48 no. 2
Type: Research Article
ISSN: 0369-9420

Keywords

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