Search results

1 – 10 of 99
Article
Publication date: 8 May 2018

Fatma A. Mohamed, Saadia A. Abd El-Megied, Mahmoud S. Bashandy and Hassan M. Ibrahim

This study aims to synthesise and characterise new reactive dyes based on thiazole derivatives which act as chromophoric moieties. These dyes were applied to cotton fabric…

Abstract

Purpose

This study aims to synthesise and characterise new reactive dyes based on thiazole derivatives which act as chromophoric moieties. These dyes were applied to cotton fabric, resulting in the dyed fabrics exhibiting good colour strength, light fastness and other fastness properties. The antibacterial activity of the dyed cotton fabric was evaluated against gram-negative and gram-positive bacteria.

Design/methodology/approach

The dyes were synthesised in two steps. First, the coupling compound was formed by adding H-acid solution to cyanuric chloride in an ice bath at pH 5 then adding 4-aminobenzenesulphonic acid portion-wise at room temperature and at pH 6-7. Second, different diazonium salts 4-phenylthiazol-2-amine (2a) and 4-(4-methoxyphenyl) thiazol-2-amine (2b) were coupled with the coupling compound at pH 5. The resultant monochlorotriazine (MCT)-reactive dyes (6a, 6b) were formed. The synthesised dyes were applied onto cotton fabric under typical exhaust dyeing conditions and their dyeing properties were investigated.

Findings

High antimicrobial activity, dye exhaustion and fixation yield on cotton fabric were recorded for each dye. All dyes showed high stability against washing, rubbing, perspiration and light fastness.

Research limitations/implications

Dyeing of cotton fabric with these dyes which have higher fastness, higher exhaustion and higher antibacterial activity is considered one of the most important reactive dyes species.

Practical implications

The preparation procedure showed the synthesis of the novel MCT-reactive dyes derived from thiazole derivatives followed by the application of these dyes on cotton fabrics.

Social implications

Use of reactive dyes will bring a number of benefits to society including higher fastness and higher antibacterial activity so, and these dyes can be used for dyeing cotton.

Originality/value

In this work, the new reactive dyes derived from thiazole derivatives were synthesised and their structures were confirmed by the analytical and spectral data. Such compounds are considered to be excellent reactive dyes with different colour shades and higher antibacterial activity.

Details

Pigment & Resin Technology, vol. 47 no. 3
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 20 March 2009

E. Abdel‐Latif, F.A. Amer, M.A. Metwally and M.E. Khalifa

The purpose of this paper is to synthesise some new 5‐arylazothiazole disperse dyes and study their application in dyeing polyester fibres.

Abstract

Purpose

The purpose of this paper is to synthesise some new 5‐arylazothiazole disperse dyes and study their application in dyeing polyester fibres.

Design/methodology/approach

A series of 5‐arylazo‐2‐(arylidenehydrazino)‐4‐substituted‐thiazole dyes were prepared by cyclocondensation of hydrazonoyl bromides with various thiosemicarbazone derivatives.

Findings

The dyed fibres exhibit very good washing, perspiration, sublimation and light fastness properties with little variation in the moderate to good rubbing fastness. The ease of preparation and the acceptable fastness properties makes these dyes particularly valuable.

Research limitations/implications

In the present paper, the synthesis of 5‐arylazo‐2‐(arylidenehydrazino)‐thiazole disperse dyes was achieved by one step pathway. In addition, the variations in substituents on the aryl and thiazole moieties could also be studied.

Practical implications

The new arylazo‐thiazole disperse dyes are superior in terms of yield, purity, colour strength, and having fastness properties of an order acceptable for commercial utilisation.

Originality/value

The synthesised disperse azo dyes are superior in terms of preparation, yield, purity, and fastness properties.

Details

Pigment & Resin Technology, vol. 38 no. 2
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 7 November 2008

M.H. Helal, G.H. Elgemeie and D.M. Masoud

This paper's aim is to evaluate the dyeing performance of newly designed azo dye system based on thiazole substituted for improved dyeing when applied to synthetic fibres.

Abstract

Purpose

This paper's aim is to evaluate the dyeing performance of newly designed azo dye system based on thiazole substituted for improved dyeing when applied to synthetic fibres.

Design/methodology/approach

For improved dyeing qualities, various azo dye systems were synthesised based on polyfunctionally substituted thiazole as the coupling component. The heterocyclic moiety was coupled with diazotised aromatic amines to afford the respective azo or hydrazono systems. The structure of the novel systems was elucidated based on elemental analysis and spectral data. Dyeing performance, electronic spectra and optical properties were characterised based on UV and K/S measurements. Fastness properties were evaluated.

Findings

The novel systems were designed so that the functionalities located on the heterocyclic ring afforded structure modification that led not only to good dispersion but also to improved adherence on the fibre. The location of the sites led to constructing a resonating system with higher electron mobility and higher absorption maxima.

Research limitations/implications

The azo dyes, used in the present context were synthesised via a step‐wise pathway leading to new dyes. In addition, the variations in substituents and location of sites on the heterocyclic core could also be studied.

Practical implications

The novel azo dye systems based on polyfunctionally substituted thiazole provided a simple practical access to a series of azo dyes with improved dyeing properties. The availability of starting materials, the simplicity and efficiency to production in good yields and high purity lead to valuable achievements for commercial production.

Originality/value

The designed azo dye systems could find numerous applications as disperse dyes in the fields of dyeing, printing and surface coating. Moreover, the systems can find applications as reactive dyes for wool, silk and cellulosic fibres.

Details

Pigment & Resin Technology, vol. 37 no. 6
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 1 October 2001

M.H. Helal

Two series of azo dye systems are considered, namely, 2‐amino‐arylazo‐4‐phenylthiazole axo dye systems 4a,b,c,d,e, and 3‐methyl‐1‐phenylpyrazolone azo dye systems 8a‐d. The…

Abstract

Two series of azo dye systems are considered, namely, 2‐amino‐arylazo‐4‐phenylthiazole axo dye systems 4a,b,c,d,e, and 3‐methyl‐1‐phenylpyrazolone azo dye systems 8a‐d. The shifts of ultraviolet‐visible absorption maxima affected by the structural configuration of the thiazole and pyrazole dye systems are investigated. The structural effects of the polyfunctionaIly substituted thiazole and pyrazole dye systems on the intensity of colour and fastness properties of the dyed fabrics are also discussed. The data of these studies are listed.

Details

Pigment & Resin Technology, vol. 30 no. 5
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 1 December 2002

E.H. El‐Mossalomy and A.A. Ibrahim

Cu(II) complexes with some hydroxy azo compounds derived from thiazole and benzothiazole have been synthesized. The structures of the complexes are inferred from data of elemental…

Abstract

Cu(II) complexes with some hydroxy azo compounds derived from thiazole and benzothiazole have been synthesized. The structures of the complexes are inferred from data of elemental analysis, electronic, IR and H1 NMR spectra. It is found that the Cu(II) coordinated to ligands through the nitrogen atom of azo group and hetero ring. This coordination lead to lower the energy of CT transition of ligands. The effect of molecular structure of the ligands and nature of the metal ion on complex formation are also examined. The free energy and stability constant of complexes formed in solution have been determined spectrophotometrically. Thiazole azo dyes were found to behave as an inhibitor with respect to the corrosion of copper in acidic solutions.

Details

Pigment & Resin Technology, vol. 31 no. 6
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 7 November 2016

H.E. Gaffer, S. Shaaban, N.A. Abed and E. Abdel-latif

This paper aimed to synthesise some new selenium-containing pyrazole, thiazole and thiophene dyestuffs and investigate their application in dyeing polyester fabrics.

Abstract

Purpose

This paper aimed to synthesise some new selenium-containing pyrazole, thiazole and thiophene dyestuffs and investigate their application in dyeing polyester fabrics.

Design/methodology/approach

4,4′-Diselanediyl-bis-(2-methoxyaniline) was diazotized by acetic acid/sodium nitrite and coupled with active methylene components such as malononitrile, ethyl cyanoacetate and ethyl acetoacetate, and their corresponding hydrazono products were cyclised with hydrazine or phenyl hydrazine to obtain a series of arylazo-pyrazole dyestuffs. Furthermore, diazo-coupling reactions of the diazotized 4,4′-diselanediyl-bis-(2-methoxyaniline) were developed to obtain a new series of 2-amino-5-arylazo-thiazole- and 4-aryazo-3-hydroxy-2-substituted thiophene dyestuffs.

Findings

The structure of the synthesised dyestuffs was established and confirmed based on their elemental analysis and spectral data (infrared, proton nuclear magnetic resonance and mass spectroscopies). The synthesised selenium-containing dyestuffs were applied as disperse dyes on polyester fabrics by high temperature-pressure technique. The dyeing characteristics of these dyestuffs were evaluated, and they were found to exhibit good fastness properties.

Originality/value

A series of symmetrical diselenide dyestuffs containing pyrazole, thiazole or thiophene coupler components were synthesised. The authors studied their application for dyeing polyester fabrics; they are superior in terms of preparation, yield, purity and fastness properties.

Details

Pigment & Resin Technology, vol. 45 no. 6
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 1 June 2001

Yehya Mahmoud Elkholy, Maher Helmy Helal and Ayman wahba Erian

Describes the synthesis and testing of a group of dyes, derived from heterocyclic compounds containing thiazole ring systems. Gives a comparative analysis of the dyes’ washing…

312

Abstract

Describes the synthesis and testing of a group of dyes, derived from heterocyclic compounds containing thiazole ring systems. Gives a comparative analysis of the dyes’ washing, perspiration and rubbing fastness when applied to synthetic fabrics.

Details

Pigment & Resin Technology, vol. 30 no. 3
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 29 June 2012

M.S. Yen

The purpose of this paper is to investigate some novel bis‐hetaryl dyes containing both azo and azo methine chromophores on their molecular structures: two series of different…

Abstract

Purpose

The purpose of this paper is to investigate some novel bis‐hetaryl dyes containing both azo and azo methine chromophores on their molecular structures: two series of different molecular structures of these dyes were synthesised. The spectral characteristics and the relationships between colour and constitution of these dyes in solvents with different polarities were systematically investigated and discussed.

Design/methodology/approach

A series of novel bichromophoric dyes containing azo and azomethine chromophores were synthesized using two kinds of reaction routes. 2‐amino‐4‐(p‐substituted) phenyl‐thiazole derivatives, which are coupling components, were subjected to diazotisation with aniline derivatives and then to condensation with benzaldehyde derivatives. By exchanging the synthesis route, two series of bichromophoric dyes could be obtained.

Findings

The maximum absorption wavelengths of the obtained dyes would be attributed to the higher bathochromic shift in basic organic solvent with high polarity, such as dimethylformamide, as compared with the solvent with low polarity, such as chloroform.

Research limitations/implications

In the present study, a series of novel bichromophoric dyes were synthesized by means of two‐step pathway. In addition, the effects of substituent on the primary aromatic amine and on benzaldehyde moieties will also be discussed.

Practical implications

This novel synthesis method of the thiazole ring would lead to the formation of 2‐amino‐4‐(p‐substituted)phenyl‐thiazole with heteroaromatic coupling component position at C‐5, and consequently would produce the heteroaromatic diazo component at C‐2 for the preparation of the heteroaryl diazo dyes.

Originality/value

In this paper, the bichromophoric dyes obtained by different synthesis routes would indicate that the effect of solvent polarity should be responsible for the bathochromic shifts of the dyes.

Details

Pigment & Resin Technology, vol. 41 no. 4
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 10 August 2018

Juan Tan, Yanfei Wang, Mouwu Liu and Jing Liu

The purpose of this paper is to study the tribological properties of a thiazole derivatives (T561), overbased alkyl benzene calcium sulfonate (T106A) compounded with T561 and…

Abstract

Purpose

The purpose of this paper is to study the tribological properties of a thiazole derivatives (T561), overbased alkyl benzene calcium sulfonate (T106A) compounded with T561 and overbased alkyl benzene magnesium sulfonate (T107) compounded with T561 in rapeseed oil (RSO).

Design/methodology/approach

A four-ball machine was used to evaluate the tribological properties of each compound and their combinations with T561 in RSO. Scanning electron microscopy, EDX and X-ray photoelectron spectroscopy were applied to analyze the tribofilm formed on the worn surfaces.

Findings

Results of tribotesting demonstrated that synergistic effects exist between the overbased sulfonates, T106A and T107, and the thiazole derivative, T561. The texts of tribofilm indicated that iron sulfide and iron oxides exist in T561 single agent lubricant film and two composite additives lubricant film, and no sulfates were detected. It suggested that the addition of alkyl benzene sulfonate did not hinder the formation of iron sulfides and iron oxides. Meanwhile, CaSO4 (MgSO4) and CaCO3 (MgCO3) were detected on the worn surface of the composite additives, which were not detected on the single agent friction surface.

Originality/value

A tribofilm mainly contains CaSO4 (MgSO4) and CaCO3 (MgCO3) formed on the worn surfaces, which is responsible for excellent extreme pressure and anti-wear properties of the compound agents because of their high melting point and high shear stress.

Details

Industrial Lubrication and Tribology, vol. 70 no. 7
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 27 May 2022

Razieh Farahati, Ali Ghaffarinejad and S. Morteza Mousavi-Khoshdel

This paper aims to investigate the corrosion inhibition ability of 4–(4-nitrophenyl) thiazol-2-amine (NPT) on the copper in 1 M HCl.

Abstract

Purpose

This paper aims to investigate the corrosion inhibition ability of 4–(4-nitrophenyl) thiazol-2-amine (NPT) on the copper in 1 M HCl.

Design/methodology/approach

The corrosion inhibitory ability of NPT on the copper in 1 M HCl was studied by electrochemical impedance spectroscopy, scanning electron microscopy and atomic force microscopy. Theoretical calculations (molecular dynamics simulation, density functional theory and the nucleus independent chemical shift [NICS] as aromaticity indicator of the molecule) were also performed.

Findings

The corrosion inhibition efficacy of this compound was about 80%. Nyquist plots display a small arc contributed to the film or oxide layer resistance and a large loop associated with charge transfer resistance. The inhibitor adsorption was under Langmuir’s adsorption model. ΔG0ads values point to the presence of physical and chemical adsorption. Results of quantum chemical calculations showed that NPT has better interaction with copper than NPTH+. NICS of NPT in benzene or thiazole rings was less negative compared to NICS of NPTH+. Thus NPT shows less aromaticity compared with NPTH+, showing NPT can have better interaction with copper than NPTH+. NPT had more negative Eint value and more interactions with the Cu relative to NPTH+, this result was in agreement with the results of quantum chemical calculations.

Originality/value

NPT is an efficient corrosion inhibitor for copper in HCl. Theoretical calculations showed that NPT can have better interaction with copper than NPTH+. The results of the theoretical studies were in good agreement with the experimental studies.

Details

World Journal of Engineering, vol. 20 no. 6
Type: Research Article
ISSN: 1708-5284

Keywords

1 – 10 of 99