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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 purpose of this study to investigate the synthesis of new Cr(III), Fe(III), Ni(II) and Cu(II) Schiff base complexes by a simple technique (microwave technique). The evaluation of the prepared complexes as pigments as corrosion resistant was also explored.

The Schiff base complexes were prepared by using microwave method (green chemistry), and then, the physico-chemical requirements according to standards for the synthesised pigments were investigate.

The prepared complexes exhibit good physical, mechanical and corrosion properties as pigments in paint formulations.

The simple technique used for synthesis of metal complex pigments will significantly increase the cost saving for the manufacturing of such pigments category. Also, the used technique is considered a green method (eco-friendly), as there no organic solvent was used.

The evaluation of the prepared complex pigments as corrosion resistants was also studied.

It is a simple technique, green synthesis (no solvent used) is involved and high yield is obtained.

The purpose of this paper is to develop a number of new anti‐fouling agents that are friendlier to the environment.

Seven copper(II) and cobalt complexes of 3‐(2‐furylidene) hydrazine‐5,6‐diphenyl‐1,2,4‐triazine (L) were prepared by interacting 3‐(2‐furylidene) hydrazino‐5,6‐diphenyl‐1,2,4‐triazine (L) with cobalt(II) and copper salts. The structures of the prepared complexes were confirmed by elemental analyses, IR and nujol mull electronic spectra, as well as magnetic susceptibility measurements. The anti‐fouling activity was measured on barnacle larvae.

The in vitro toxicity of the organic ligand and its cobalt and copper complexes on barnacle larvae was measured. The results indicated that the toxicity of the ligand increased upon complexation and that copper complexes are the most active ones.

Successful development of some new copper(II) and cobalt complexes of 1,2,4‐triazine that have in vitro anti‐fouling activity against barnacle larvae and might be safe to the marine environment.

This paper aims to report on the synthesis and characterisation of new flame retardants and anticorrosive additives based on Schiff’s base compounds, which were added physically to organic coating.

Flame retardants are incorporated into polymeric materials either as additives or as reactive materials. Additive-type flame retardants are widely used by incorporating into polymeric materials by physical means. In this research, Schiff’s base (azomethine) compounds are added physically to alkyd paint as flame-retardant additives. Elemental analysis, infrared spectroscopy and proton nuclear magnetic resonance spectroscopy were used to characterise the structure of the prepared Schiff’s base compounds. Thermal gravimetric analysis was used to evaluate their thermal stability. Experimental coatings were manufactured on a laboratory scale, and then applied by brush on wood and steel panels.

Results of an oxygen index value indicated that alkyd paints containing Schiff’s base compounds as additives exhibit very good flame-retardant effects. Also the physical, mechanical and corrosion resistance properties were studied to evaluate the drawbacks of the additives. The additives did not affect the flexibility of the paint formula. The gloss and the impact strength were decreased by the additives, but the hardness, adhesion and corrosion resistance were significantly improved by these additives.

Alkyd resins are the most extensively used synthetic polymers in the coating industry. Nitrogen compounds are a small but rapidly growing group of flame retardants which are in the focus of public interest concerning environment-friendly flame retardants. So, the focus of this study is on Schiff’s base compounds as flame retardants and anticorrosive additives for alkyd resins to assess their applicability.

Schiff’s base compounds can be used as new additives in paint formulations to improve the flame-retardant and corrosion properties.

In recent years, there has been considerable interest in the nitrogen-based family of materials because they not only have a wide range of thermal and chemical stabilities, but can also provide improved thermal and flame-retardant properties to polymers. The present paper reports on the synthesis and characterisation of Schiff’s base compounds and their performance in alkyd resin coatings.

The paper aims to the preparation of novel disperse dye based on azo salicylaldehyde derivatives TF-A [2-hydroxy-5-((3-(trifluoromethyl)phenyl)diazenyl)benzaldehyde] and full evaluation of their use as disperse dye TF-ASC [bis 2-hydroxy-5-((3-(trifluoromethyl)phenyl)diazenyl)benzaldehyde Schiff base with 4,4'-methylenedianiline] for dyeing polyester fabric at various conditions.

The dispersed dye was synthesized via Schiff base condensation in the presence of ceric ammonium nitrate cerium ammonium nitrate 10 mmole% as an eco-friendly catalyst at room temperature. The chemical structure of the prepared dye was characterized via elemental analysis, Fourier-transform infrared spectroscopy, 1H- and 13 C-NMR spectroscopic analysis tools. This study thoroughly examined the dyeing of disperse dye TF-ASC on polyester at various conditions. The characteristics of dyed polyester fabric were measured by colour measurements, as well as light, washing, crock fastness and finally, colour strength. The discrete fourier transform (DFT) theoretical studies, including E_HOMO, E_LUMO and optimized geometrical structure, were assumed and discussed in detail.

The results showed that the synthesized organic dye TF-ASC was highly functional and appropriate for this kind of dyeing method. The dyeing fabrics obtained from disperse dye TF-ASC, properties possess high colour strength as well as good overall fastness properties. These dyes had a high affinity for polyester fabric, with just a tiny change in dye affinity when the pH was changed, even under alkaline circumstances. The dye levelness and shade depth of the colour results were good, and there were a variety of hues from light brownish yellow to deep brownish yellow. The results obtained from DFT computational studies such as E_HOMO, E_LUMO, optimized structure, diploe moment µ and electrophilicity index deduced that prepared organic dye TF-ASC is more applicable as a dispersed dye.

This research is significant because it provides a new dye for dyeing polyethylene terephthalate fibres with exceptional brightness and levelness; the method of preparation is a useful pathway due to its being known as a green chemistry method.

This paper aims to focus on the synthesis of the macrocyclic complexes (Cu and Zn) and their applications as anticorrosive materials in epoxy paint formulation for surface coating application.

A selected macrocyclic Cu(II) and Zn(II) complexes were prepared via template synthesis and characterized using Fourier transform infrared, thermal gravimetric analysis, scanning electron microscope, flexibility, hardness and adhesion of coating films prepared using epoxy paint.

The corrosion resistance of the epoxy-painted films was improved due to the incorporation of the Zn and Cu complexes into the formulation.

It was found that the metal complex-based formulation with Cu(II) and Zn(II) had outperformed the sample blank.

This paper aims to synthesize new screen-printing ink formula based on new derivatives of azo thiadiazol disperse dyes and evaluate their characteristics after being printed on polyester fabric substrates.

New dispersed dyes based on 1, 3, 4-Thiadiazole derivatives (dyes 1 and 2) were prepared and confirmed by different analyses, infrared (IR), mass and nuclear magnetic resonance (NMR) spectroscopy, and then formulated as colored materials in the screen-printing ink formulations. Printing pastes containing the prepared dyestuffs and other ingredients were used for printing polyester using screen-printing or traditional printing. The characteristics of printed polyester fabric substrates were measured by color measurements such as a*, b*, L*, C*, E, Ho, R% and color strength, as well as light, washing, crock and alkali perspiration fastness, and finally, the depth of penetration was evaluated.

The prepared 1, 3, 4-Thiadiazole derivatives (dyes 1 and 2) were obtained from the reaction of 5,5’-(1,4-phenylene)bis(1,3,4-Thiadiazole-2-amine) with resorcinol and m-toluidine as a coupling component. The suitability of the prepared dyestuffs for silk screen-printing on polyester fabrics has been investigated. The prints obtained from a formulation containing dye 1 possess high color strength as well as good overall fastness properties if compared to those obtained using dye 2.

The method of synthesis of the new dyestuffs and screen-printing ink provides a simple and practical solution to prepare some new heterocyclic disperse azo dyes, and they are formulated in the screen-printing inks for printing on a polyester fabric substrate.

The prepared disperse dyes based on 1,3,4-Thiadiazole derivatives (dyes 1 and 2) could be used in textile printing of polyester on an industrial scale.

Paper aims to preparation of new acid disperse dyes based on thiadiazol derivatives and evaluation of their use as antimicrobial colorants in digital transfer-printing ink formulations for printing onto polyester fabric substrates.

New disperse dyes based on 1,3,4 - thiadiazol derivative (dyes 1–3) were prepared and evaluated by different analysis then formulated as colored materials in the ink formulations. The viscosity, dynamic surface tension and particle size distribution of the prepared inks were measured. The printed polyester fabric substrates were tested using a variety of tests, including light fastness, washing, alkali perspiration and Crock fastness, as well as depth of penetration. Density-functional theory (DFT) calculations were carried out at the Becke3-Lee-Yang-parr (B3LYP) level using the 6–311** basis set, and the biological activity of the prepared disperse dyes was investigated.

The obtained results of the physical of the prepared ink revealed that thiadiazol disperse ink is a promising ink formulation for polyester printing and agrees with the quality of the printed polyester fabric. The optimization geometry for molecular structures agreed with the analysis of these compounds. The HOMO/LUMO and energy gap of the studied system were discussed. The molecular docking analysis showed strong interaction with DNA Gyrase and demonstrated to us the high ability of these inks to act as antimicrobial agents.

The prepared inks containing the prepared thiadiazol disperse dye were high-performance and suitable for this type of printing technique, according to the results. The prepared inks resist the growth of microorganisms and thus increase the ink's storage stability.

The prepared disperse dyes based on 1,3,4 - thiadiazol derivative (dyes 1–3) can be a promising colorant in different applications, like some types of paint formulations and as a colorant in printing of different fabric substrates.

Acrylamide is a compound found in several food products. Due to the toxicity of this compound, research also seeks strategies to modify industrial and homemade processes, impacting on the reduction of the compound. This paper aims to discuss the aspects surrounding the presence of acrylamide in foods.

Published literature on the presence of acrylamide in foods and on its effects has been reviewed. This paper explores the importance of this compound, summarizes the knowledge of its formation and gathers data on its incidence in food and the possibilities of mitigation. Special attention is given to an evaluation of the toxicological tests applied, to analyze whether acrylamide can be considered as a food safety problem.

Human exposure to food with high levels of acrylamide varies in their levels regarding the consumption of food in the diet and not only by the level of the compound present in them. Although the compound is well defined as toxic to humans, the association between its intake and most common cancers may not be directly related.

Depending on the approach of the researchers, contradictory results are obtained, showing the importance of this topic to the development of healthy food products. Further research is still needed to validate the potential effects of acrylamide on human health.