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The preparation and characterisation of new bioactive polymeric materials.

New bioactive polysaccharide were prepared by grafting of acrylonitrile onto water soluble starch and then reacting with bioactive heterocyclic rings. The biological activity, against bacteria, of the materials prepared was studied.

Some of the prepared bioactive materials show high disinfecting power against bacteria.

The bioactive materials were prepared by grafting acrylonitrile onto starch and then reacting the resulting material with cyanuric acid and 2‐aminothiazole. Many other heterocyclic rings that contain tertiary nitrogen atom or amide nitrogen can also be used.

The new bioactive materials prepared can be used for disinfecting purposes.

Some of the materials prepared were used successfully in killing bacteria, as such, can be used as disinfecting materials.

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.

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.

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.

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.

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.

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.

The present study aims to focus on the possibility of developing new eco-friendly azo dyes with good colouristic application properties, exhibiting biological and pharmacological activities.

Coupling of 4-hydroxycoumarin with a variety of aromatic diazonium salts of 2-aminothiazole, 2-aminobenzothiazole, 4-aminoantipyrine, 4-aminoacetophenone, adenine sulphate, a-naphthylamine and sulphadimidine to produce novel azo dyes. The compounds were fully characterised using spectroscopic and analytical methods. All of the compounds were tested for their antimicrobial, anticancer and antioxidant activities. The prepared dyestuffs were dyed on polyester fabrics and subsequently their dyeing properties, light, washing, perspiration, rubbing and sublimation fastness were determined.

The spectroscopic data of the synthesised compounds have provided decisive evidence that such compounds exist in the solid state as the azo-dike to form C and in solution in equilibrium tautomer forms A, B and D. The prepared dyestuffs are suitable for either heat transfer printing or traditional printing on polyester and nylon 6 fabrics. The prints obtained from the dyes possess high colour strength, as well as good overall fastness properties. Also the synthesised compounds exhibit good biological and pharmacology activity.

Synthesis of these seven azo dyes for textile dyeing had never been reported previously.

The dyestuffs derived from 4-hydroxycoumarin are reasonable azo disperse dyestuffs giving good all round fastness properties on polyester fabrics.

Production of less expensive and new eco-friendly dyes exhibit antimicrobial and anticancer activity.

It provided a potentially simple way to synthesize novel coumarin azo-dyes exhibit good biological and pharmacology activity and also exhibit good overall fastness properties.

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

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.

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.

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.

This study aims to focus on the possibility of developing new thiazole azo dyes with good colouristic application properties, biological and pharmacological activities.

Coupling of curcumin with different aromatic diazonium salts of 2-amino thiazole derivatives, such as 2-aminobenzothiazole, 2-amino-5-phenylthiazole, 2-amino-5-methylthiazole and 2-amino-5-nitrothiazole-produced novel azo dyes. Structures of all synthesised dyes were fully confirmed via spectroscopic and analytical methods. Those compounds were examined for their antimicrobial, anticancer and antioxidant activities. They were applied on polyester fabrics and, subsequently, their dyeing properties, light, washing, perspiration, rubbing and sublimation fastness were determined.

Prepared dyestuffs were suitable for dyeing polyester fabrics. It was found that all prepared dyes possess high colour strength, as well as good overall fastness properties. Meanwhile, the synthesised compounds exhibited good biological and pharmacology activity.

Synthesis of these four azo dyes for textile dyeing was not conveyed earlier.

Thaizolyl disperse dyes were responsible for giving better colour assessment and fastness properties on polyester fabrics.

Although, most of synthesis eco-friendly dyes are expensive, they are showing a good antimicrobial and anticancer activity.

It gave straightforward approach to synthesise novel thiazolyl azo dyes with good biological, pharmacology activities, good colour assessment, and fastness properties.

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.

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.

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.

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.

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.

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.

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.

To synthesize some new heterocyclic disperse azo dyes and their utilization in textile printing.

To prepare 1‐cayno‐1‐substituted aryl azo‐2‐methyl benzothiazole by the reaction of 2‐aminothiophenol with malononitrile and the end product coupled with different diazonium salts. The prepared dyestuffs are established using element analysis, IR measurements, ¹H‐NMR and Mass spectra. Printing pastes containing the prepared dyestuffs and a thickener were used for printing polyester and/or nylon 6 using either transfer printing or traditional printing.

New selected arylazo cyanomethyl benzothiazole dyes were obtained from the reaction of diazotized aniline derivatives with 2‐cyanomethyl benzothiazole as a coupling component. The suitability of the prepared dyestuffs for either heat transfer printing or traditional printing on polyester and nylon 6 fabrics has been investigated. The prints obtained from dyes containing non polar groups which have sublimation properties possess high colour strength as well as good overall fastness properties if compared to those obtained using dyes containing polar groups.

The new heterocyclic disperse azo dyes were prepared from 2‐cyanomethylbenzothiazole and were utilized in preparing pastes for textile printing to print polyester and nylon 6 fabrics. In addition, the variation in substituents on the synthesized dyes could also be studied.

The method of synthesis of the new dyestuffs provides a simple and practical solution to prepare some new heterocyclic disperse azo dyes with low molecular weight, suitable for sublimation in heat transfer printing methods.

The methods for synthesis of the new heterocyclic disperse azo dyes are simple. These dyestuffs could be used in textile printing of polyester and nylon 6 on an industrial scale.

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

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

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.

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.

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.

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

The purpose of this paper is to evaluate the dyeing performance of newly designed and synthesised azo dye systems based on polyfunctionally substituted oxopyridine core for improved dyeing when applied to synthetic fibres.

For improved dyeing qualities, various azo dye systems were synthesised based on polyfunctionally substituted oxopyridine core as the coupling component. The heterocyclic moiety was coupled with diazotized aromatic amines or diazotized tetrahydrobenzothiophenes to afford the respective azo or hydrazono systems. Other counterparts were obtained via treatment with different reagents. 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 also evaluated.

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

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

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

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

Like aqueous corrosion of metals, atmospheric corrosion of metallic articles has also been a matter of great anxiety due to the individual and joint action of oxygen, humidity and various types of pollution gases and ions in the atmospheres. As there is no limit of oxygen availability in the open atmosphere, this type of corrosion of metals is mainly controlled by humidity. In industrial mines and marine environments, however, metal attack is controlled by aggressive gases, ions and chloride ions respectively.