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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.

Heterocyclic aromatic amines are mutagenic and/or carcinogenic compounds formed during cooking of meat. Therefore, the formation levels of them should be reduced. For this aim, the purpose of the present study was to determine the effect of dry breadcrumb in meatball production on the formation of heterocyclic aromatic amines. In addition, the effect of dry breadcrumb on some quality parameters of the meatballs was also investigated.

Meatball dough with 15 percent fat was divided into four parts, where one group was selected as the control group (without dry breadcrumb). In the other three groups, dry breadcrumb was added in various ratios of 5 percent, 10 percent and 15 percent (w/w). Then, meatball dough was stored at 4 °C for 3 h and shaped into meatballs with a metal shaping device (7 × 1 cm). For some of the quality parameters, water, pH, cooking loss and TBARS analyses were done in the samples. Heterocyclic aromatic amine analysis was done in only cooked samples according to solid phase extraction.

The use of dry breadcrumb in meatball production decreased water content and cooking loss. As cooking temperature increased, water contents and cooking loss of meatball decreased. PhIP, AαC and MeAαC were not detected in any of the samples analyzed. As cooking temperature increased, total amount of HCAs increased and ranged between 0.05 and 0.51 ng/g. While the use of dry breadcrumb in the meatball production increased IQ content of the meatballs, the use of 5 percent dry breadcrumb caused a decrease in the total HAA content (28.57–66.67 percent) for all cooking temperatures.

Many research studies including our study in the literature were conducted on formation and reduction of HAAs in meat and meat products. However, although dry breadcrumb is frequently used both in domestic and commercial meatball formulations; to the best of our knowledge, effect of using dry breadcrumb in meatball production on HAAs formation has not been investigated in the literature. Therefore, in the present study, the effects of the use of dry breadcrumb in meatball production on some quality parameters and formation of HAAs in meatballs cooked at 150 °C, 200 °C and 250 °C were determined.

Work reported in the present paper investigated the inhibiting properties of a number of N‐heterocyclic amines in 0.1 mol/l HClO₄. An attempt also was made to correlate some molecular parameters of these compounds with their corrosion inhibitor efficiency.

The test series included piperidine (pip), 2‐methylpiperidine (2mp), 3‐methylpiperidine (3mp), cis‐2,6‐dimethylpiperidine (26dp), 3,5‐dimethylpiperidine (35dp), 3‐hydroxy piperidine (3hp), 4‐hydroxypiperidine (4hp), 4‐aminopiperidine (4ap), piperazine (pz), 2‐methylpiperazine (2mpz) and cis‐2,6‐dimethylpiperazine (26dpz). The inhibiting effect was investigated in 0.1& mol/L HClO₄ by potentiodynamic polarization (DC) and electrochemical impedance spectroscopy (EIS).

The results show that these compounds suppressed both cathodic and anodic processes of iron corrosion in 0.1 mol/l HClO₄ by adsorption on the surface, which followed a Langmuir adsorption isotherm. Experimental observations indicated that basic piperidine and piperazine were better corrosion inhibitors than were their derivatives. The inhibition properties of N‐heterocyclic amines were found to be related to the charge on the nitrogen atom and the sum of the net charge of the all six atoms from the cyclic ring.

This paper provides useful information relative to corrosion inhibition efficiency of the group of N‐heterocyclic amines. It is concerned with a theoretical explanation between electronic and structural characteristics of these compounds and their inhibitor efficiency.

The phosphorus and zinc contained in zinc dialkyl dithiophosphate (ZDDP) caused severe environment pollution and catalyst poison. Thus, the phosphorus-free additive, such as borate esters, has become one of studying hot topics in the area of oil additive. However, the stability of hydrolysis greatly limited the use of borate esters. The purpose of this paper is to improve the stability of hydrolysis by synthesizing a new kind of N-containing heterocyclic borate ester (MTTDB) as a lubricant additive.

The tribological properties of novel borate ester (MTTDB) as an additive in the base oil were studied by a four-ball machine. The element composition and chemical state of the tribofilm were investigated by scanning electron microscopy, energy dispersive spectrometer and X-ray photoelectron spectroscopy.

The results showed that the base oil lubricated by MTTDB exhibited high hydrolytic stability, good anti-wear property and excellent extreme pressure performance. When 2.5 per cent MTTDB was added into the 100N base oil, the smallest wear scar diameter (0.46 mm) was obtained. Furthermore, the decomposed borate ester, organic sulfide adsorbed on the worn surface was detected, and S element reacted with the steel surface and generated FeSO4, both of which contributed to the formation of the tribofilm.

Based on N-containing heterocyclic compounds, for instance, thiadiazole derivatives, introducing nitrogen and sulfur elements into borate ester, a new kind of N-containing heterocyclic borate ester (MTTDB) exhibited excellent property in hydrolysis stability, friction-reducing, anti-wear and extreme pressure. This synthesized method would be helpful for the borate ester used as additive in engine oil, gear oil and other industrial lubricants.

Self-organization has been regarded as a tool for the synthesis of well-defined organic nanostructures. Heterocyclic annulated perylene diimides are the subjects of considerable current research studies. The purpose of this study is to reveal the photophysical property, electronic structure and solid-state packing of O-heterocyclic annulated perylene diimide.

Asymmetrically five-membered O-heterocyclic annulated perylene diimide (OAPDI) was synthesized. Structure and purity of OAPDI were confirmed by ¹H NMR, ¹³C NMR, IR and mass spectral techniques. Photophysical properties of OAPDI were studied using UV–vis absorption and fluorescence in both solution (CHCl₃) and solid state. Scanning electron microscopic and atomic force microscopy were used to characterize the surface morphology of OAPDI. Conducting properties of the OAPDI were evaluated by current–voltage measurements. The compounds geometries were also optimized at 6-31G* using density functional theory.

The UV–vis absorption and fluorescence spectra of OAPDI in solution are blue-shifted in comparison with that of unsubstituted perylene bisimide. Solid-state UV–vis measurements of OAPDI indicate that it is capable of forming highly ordered structure. The non-covalent interactions, electrostatic attraction and p-p stacking moieties of OAPDI synergistically guide assembly and domain growth while maintaining the interpenetrating network of nanofibers in the solid film. The OAPDI gave higher current at −2.0 V (0.68 µA) and 4.0 V (1.0 µA).

This study will be helpful for exploring feasible routes to acquire soluble perylene diimides and well-defined organic nanostructures. Furthermore, such molecular tailoring approach would be helpful for designing and synthesizing novel organic semiconductive materials with excellent charge-transporting and light-emitting capabilities.

Aluminium and zinc pigments react in aqueous alkaline media (e.g. water‐borne paints) by the evolution of hydrogen which can be measured gasvolumetrically. Certain organic heterocycles are well‐known corrosion inhibitors for different metals. The six different heterocyclic compound which were examined inhibited the corrosion reaction of zinc pigment in aqueous alkaline media. The most efficient inhibitors were 1H‐benzotriazole at pH 8 and 10 and 2‐(5‐aminopentyl)benzimidazole only at pH 10. In contrast, with addition of all heterocycles there was no corrosion inhibition on aluminium pigment. This complete difference in the corrosion inhibiting effect of the heterocycles with respect to the two different metal pigments can be explained with Pearson’s “Principle of Hard and Soft Acids and Bases”.

Epoxy resins are compounds which contain in their molecule more than one 1,2 epoxy group capable of undergoing polyreactions, referred to as curing reactions. The presence of epoxy groups may be either internal, terminal or on cyclic structures. Polyreactions take place at varying temperatures from low room temperature cure to high temperature cure systems upon addition of curing agents such as amines, amides or carboxylic acid anhydrides. The uncured resins which range from low viscosity liquids to high melting solids, soluble in organic solvents, become insoluble, infusible hard materials on curing due to crosslinked structure of the cured products.

In this paper, the main aim is to study the influence of some nitrogen heterocyclic compounds, namely 2‐mercaptobenzimidazole (2‐MBI), 2‐mercaptobenzoxazole (2‐MBO) and 2‐mercaptobenzothiazole (2‐MBT) on the corrosion inhibition of copper in 0.5 M sulphuric acid.

Measurements were carried out in a three‐electrode cell that was connected to the corrosion measurement system using software for Tafel polarization. Impedance measurements were carried out at open circuit potential using an electrochemical interface and frequency response analyzer at frequencies from 100 kHz to 10 MHz.

For all the compounds, a consistent trend of increase in inhibition efficiency was observed as a function of concentration. The adsorption of all the compounds on to the copper surface in the acidic solution was found to obey the Langmuir Adsorption Isotherm. The values of activation energy and free energy of adsorption for all the compounds also were calculated. The Tafel polarization studies indicated that all the compounds were mixed inhibitors.

In order to further the performance of heterocyclic compounds and also to identify their synergistic effects with some additives (such as surfactants) it is suggested that further research into the behaviour of these heterocyclic compounds with other metals be carried out.

The results of this paper can be used for acid descaling of copper in which suitable inhibitor systems with the highest efficiencies are required.

The synthesis and chemistry of nitrogen heterocyclic azo compounds have been extensively studied. Many derivatives of this type were proved to be excellent dyes. Presents a systematic and comprehensive survey of all recently synthesised nitrogen heterocyclic azo dyes according to dyeing methods.

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.

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.

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.

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.

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.

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.