Colorimetric studies of heterocyclic monoazo reactive dyes and their dyeing applications on cotton,silk, and wool fibers

Heterocyclic quinazolinone-based hot brand monoazo reactive dyes were obtained by diazotization of 3-(4-aminophenyl)-2-phenylquinazolin-4(3H)-one and coupling with a variety of cyanurated coupling components. All the heterocyclic hot brand monoazo reactive dyes were characterized by elemental analysis (C, H, N) and by use of spectroscopic techniques (FT-IR, UV–visible, ¹H NMR). Their performance as reactive dyes was assessed on silk, wool, and cotton fabrics. The dyes were found to give a variety of color shades with very good depth and uniformity on the fibers. The fastness of all the dyes on the fibers was moderate to excellent. Colorimetric data (L*, a*, b*, C*, H*, and K/S) of the synthesized dyes were also studied in detail.     

Organic–inorganic hybrid silica film coated for improving resistance to capsicum oil on natural substances through sol–gel route

This study concerns the organic–inorganic hybrid coating of silica sol based on dyed cotton, silk and wool fabrics in order to increase the repellence to capsicum oil via adding methyltriethoxysilane, octyltriethoxysilane, hexadec-ltrimethoxysilane or tridecafluorooctyltriethoxysilane (FAS) in the inorganic silica sol. The dyed cotton fabric treated with hybrid silica sol doped with FAS (F-silica sol, FAS 4 %) presents oil-repellent capability, and the contact angles of capsicum oil on the treated cotton, silk and wool fabrics are 98.5°, 111.59° and 122.15°, respectively. A high FAS concentration (20 %) can improve the oil-repellent ability to 5 grades comparing to the untreated fabrics. The color strengths (K/S) of the coated fabrics change slightly, while the maximum absorption wavelengths of the coated fabrics are the same as the untreated fabrics. Although the drape coefficient of cotton fabric is increased to 54 % from 39 % after coated with F-silica sol, the effect is not significant. Compared to the weight gain rate of untreated cotton, silk and wool samples (1.89, 1.23 and 2.38 %), the weight gain rate of the cotton, silk and wool samples coated with F-silica sol are 6.99, 4.76 and 7.69 %, respectively. The calculated sol–gel weight gains (5.10, 3.53 and 5.31 %) of coated fabrics indicate that the silica coating is subsistent on the fiber surfaces.     

Effect of Fiber Treatment on Dimensional Stability and Chemical Resistance Properties of Hybrid Composites

In this work, oil palm empty fruit bunch (EFB) and jute fibers were treated by 2-hydroxy ethyl acrylate (2-HEA) to enhance interaction with the epoxy matrix in hybrid composites. Hybrid composites were fabricated by the hand lay-up technique by reinforcing chemical-treated oil palm EFB and jute fibers in an epoxy matrix. Physical (density, void content, water absorption, and thickness swelling) and chemical resistance properties of treated hybrid composites were characterized. Chemically treated oil palm EFB/jute fiber reinforced hybrid composites display better dimensional stability (water absorption and thickness swelling) and chemical resistance as compared to untreated hybrid composites.     

Synthesis,characterization and dyeing assessment of novel acid azo dyes and mordent acid azo dyes based on 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid on wool and silk fabrics

Novel acid mono azo and mordent acid mono azo dyes were synthesized by the coupling of diazonium salt solution of different aromatic amines with 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid. The resulting dyes were characterized by spectral techniques like elemental analysis, IR, ¹H-NMR and UV visible spectroscopy. The dyeing performance of all the dyes was evaluated on wool and silk fabrics. The dyeing of chrome pre-treated wool and silk fabrics showed better hues on mordented fabrics. Dyeing of wool and silk fabrics resulted in pinkish blue to red shades with very good depth and levelness. The dyed fabrics showed excellent to very good light, washing, perspiration, sublimation and rubbing fastness.     

Changes in the Inter- and Intra- Fibrillar Structure of Lyocell (TENCEL®) Fibers after KOH Treatment

Lyocell fibers were treated with KOH up to 8 M which was demonstrated to distribute homogeneously at the outer zones of fiber cross section compared to NaOH which accesses more deeply but less homogenously. Both NaOH and KOH solutions can be used to lower significantly the fibrillation of lyocell fibers. However, due to intrafibrillar swelling together with deep penetration ability of alkali seen for NaOH treatments results in great fiber tensile strength loss which is not observed for KOH treatments due to its inability to penetrate the fiber completely. The porous structure of fibers was studied by inverse size exclusion chromatography (ISEC) to identify mean pore diameter, total pore area and accessible pore volume (APV). Mean pore diameter of fibers decreased after KOH treatments which did not change after NaOH treatments. Wide angle X-ray diffraction analyses (WAXD) were applied to identify the crystallinity index and crystallite size. In general, fiber properties such as water retention value, carboxyl content using methylene blue sorption method, depth of color measured after dyeing with C.I. Direct Red 81 and weight loss were distinctly different in the ranges up to 2 M, 2-5 M and 5 to 8 M KOH. KOH treatment suggests new possibilities for the pretreatment of lyocell fibers to lower fibrillation while slightly lowering elongation at break without a distinct loss in tensile strength and with less decrease in carboxyl content and weight loss without changing dyeing properties of fibers compared to NaOH treatment.     

PREPARATION AND CATALYTIC ACTIVITY OF BIOACTIVE FIBERS

Two kinds of water-soluble metallophthalocyanines, binuclear cobalt phthalocyanine （Co2Pc2） and binuclear ferric phthalocyanine （Fe2Pc2）, were synthesized through phenylanhydride-urea route and characterized by elemental analysis and FT-IR spectra. Binuclear metallophthalocyanine derivatives （Mt2Pc2） were immobilized on silk fibers and modified viscose fibers to construct bioactive fibers of mimic enzyme. Mt2Pc2 was used as the active center of bioactive fibers, viscose and silk fibers as the microenvironments. The catalytic oxidation ability of bioactive fibers on the malodors of methanthiol and hydrogen sulfide was investigated at room temperature. The experimental results indicated that the catalytic activity of such bioactive fibers was closely correlative to the types ofbioactive fibers and substrates.     

Ultrasonic assisted improved extraction and dyeing of mordanted silk fabric using neem bark as source of natural colourant

Natural products with therapeutic nature are nowadays warmly welcomed in textiles. Current study is concerned with isolation of tannin from neem bark (Azadirachta indica) and its application onto silk fabric. For improvement in shades, chemical & bio-mordants have been employed at optimal dyeing conditions. It is found that methanolic extract of pH 5 obtained 8 g dye powder after US Treatment for 30 min has given high color strength if used to dye irradiated silk for 65 min at 75 °C. Bio-mordanting using herbal plants has improved the color characteristics as compared to chemical mordants used. ISO standards for color fastness reveal that herbal based bio-mordants have improved the rating from good to excellent as compared to chemical mordants used. It is concluded that US treatment has not only isolate the colorant for neem bark under mild condition but also given excellent characteristic using bio mordants onto silk fabrics.     

丝素蛋白纤维的接枝聚合Ⅲ．丝素蛋白纤维的接枝聚合染色

本文提出了通过接枝聚合物将丝素蛋白纤维的染色的设想：在染料分子上引入丙烯酰基，然后将其接枝到丝素蛋白纤维表面。将2－羟基－4－丙烯酰氧二苯酮（HAOBP），1－羟基－2－丙烯酰氧蒽醌（HAOAQ）和1，5，8－三羟基－2－丙烯酰氧蒽醌（THAOAQ）等三种染料，分别用无引发剂存在下的接枝聚合法接枝到丝素蛋白纤维表面，使丝素蛋白纤维分别染成了浅黄、浅红和浅紫三种颜色。这样染色了的丝素蛋白纤维在浓酸或浓碱溶液中回流，未发生任何裉色现象，并且其热稳定性和紫外稳定性也得到了显著的改善。力学性能未下降。采用甲基丙烯酸甲酯（MMA）与染料单体共同进行接枝聚合染色，可以提高丝素蛋白纤维的光泽度，并可将接枝整理和染色两道工序合而为一。HAOBP、HAOAQ和THAOAQ在丝素蛋白纤维上的接枝率（mol单体／g丝），具有如下顺序，HAOBP＞HAOAQ＜THAOAQ。该顺序与它们的亲水性顺序恰好相反，这一结果支持了Imoto等人的无引发剂存在下的接枝聚合发生在丝素蛋白纤维的疏水区域的观点。     

Study on microstructure and mechanical properties relationship of short fibers/rubber foam composites

Research on short fibers/rubber foam composites is rarely found in the literature. In this paper, microcellular rubber foams unfilled (MF), strengthened by pretreated short fibers (MFPS) and untreated short fibers (MFUS) are prepared, respectively. The microstructure and mechanical properties of the three composites have been studied via scanning electron microscope (SEM) and mechanical testing, respectively. The SEM results show that both pretreated and untreated short fibers disperse uniformly in the composites and in bidimensional orientation. Moreover, the pretreated short fibers have much better adhesion with the rubber matrix than untreated ones. The experimental results also indicate that the introduction of short fibers is mainly responsible for the great enhancement of most mechanical properties of the microcellular rubber foams, and the good interfacial adhesion of the short fibers with the matrix contributes to the more extensive improvement in the mechanical properties. It is also found that the reinforcement effect of short fibers to compressive modulus strongly depends on the density of microcellular rubber foams, the orientation of short fiber and the deformation ratio. The compressive modulus of microcellular rubber foams at the normalized density less than 0.70 and beyond 0.70 is predicted by the modified Simple Blending Model and the Halpin-Kerner Model, respectively. The theoretically predicted values are in good accordance with the experimental results.     

Synthesis,characterization, and dyeing performance of some azo thienopyridine and thienopyrimidine dyes based on wool and nylon

A string of novel heterocyclic mono azo dyes were synthesized and their utilization in dyeing different fabrics as wool and nylon were discussed. Thienopyridine azo dyes 4 and 6 were prepared by reaction of chloro acetamidederivative 2 with diamino compounds to yield 3 and 5 , followed by reaction with NaNO₂/HCl and coupling with nucleophilic reagent. One-pot reaction of chloro acetamide 2 with ammonium thiocyanat in solvent ethanol gave the unexpected thienopyrimidine derivative 7 , which contain two active sites, the former is primary amine that was able to form diazonium salt that coupled with N,N-dimethylaniline, resorcinol, and/or self-coupling to afford the azo dyes 8-10 , and the latter is active methylene group that underwent coupling with different diazonium salts to give the azo thienopyrimidine derivative dye 11-15 . The dyeing performance of these azo dyes had been investigated in terms of their dyeing behavior and fastness properties on different fabrics. Results showed that the color strength (K/S) values, as well as, washing, rubbing, and resistance to acid, alkali and light showed high efficiency of these heterocyclic mono azo dyes to dye wool rather than nylon fibers.     

Application of anisotropic silver nanoparticles: multifunctionalization of wool fabric

Anisotropic silver nanoparticles (NPs) were successfully employed to color the wool fabrics in this study. The modified wool fabrics exhibited brilliant colors due to the localized surface plasmon resonance (LSPR) properties of silver NPs. The colors of wool fabrics altered with the morphologies of silver NPs. These modified wool fabrics were characterized by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The results indicated that anisotropic silver NPs were effectively assembled on the surface of wool fibers when the solution pH and temperature was about 4 and 40°C, respectively. This assembling of silver NPs on the wool fibers was realized by the electrostatic interaction between wool fibers and silver NPs. This technique was also applied to gold NPs. The fabrics treated with anisotropic silver NPs showed high antibacterial activity against the bacteria of Escherichia coli. This study opens a new approach to color and functionalize conventional textile materials.     

Synthesis of heterocyclic monoazo dyes derived from 1H-benzo[g]pyrazolo[3,4-b]quinoline-3-ylamine: their antimicrobial activity and their dyeing performance on various fibers

Heterocyclic monoazobenzoquinoline-based azo dyes have been derived by diazotization of 1H-benzo[g]pyrazolo[3,4-b]quinoline-3-ylamine with a variety of phenylpyrazolone-based coupling compounds. The synthesized dyes were characterized by determination of their percentage yield, by elemental analysis, and by UV?Cvisible, IR, and ¹H NMR spectroscopy. Dyeing performance on silk, wool, nylon, and polyester fibers was assessed. The fastness properties of the dyes on each fiber were moderate to excellent. The antimicrobial activity of the dyes at different concentrations were also examined, by use of the Kirby?CBauer disk diffusion method.     

Eco-friendly and protective natural dye from red prickly pear (Opuntia Lasiacantha Pfeiffer) plant

New natural dye extracted from red prickly pear was used for dyeing wool with different types of mordents. The effect of mordant concentration on the color strength was discussed; the results obtained indicated that the color strength decreases with the increase of mordant concentration. The effect of the dye bath pH, salt concentration, dyeing temperature and dyeing time was also studied. The color strength and the dye uptake have exhibited high values. Good fastness properties of the dyed fabric were achieved.Antimicrobial activity of wool fabric dyed with this dye was tested according to diffusion agent. Test organisms as Escherichia coli, Bacillus subitilus, Pseudomons aeruginosa and Staphylococcus aureus were used and the results indicated that the samples exhibited a high inhibition zone.According to the available literature, this is the first report concerning a natural dye for fabric from fruits of red prickly pear plants.     

STUDY ON THE CATALYTIC ABILITY OF BIOACTIVE FIBERS

Two kinds of water-soluble metallophthalocyanines (Mt2Pc2), binuclear cobalt phthalocyanine (Co2Pc2) and binuclear ferric phthalocyanine (Fe2Pc2), were supported on silk fibers and modified viscose fibers to construct bioactive fibers of mimic enzyme, Mt2Pc2 used as the active center of bioactive fibers, viscose and silk fibers as the microenvironments. The catalytic oxidation ability of bioactive fibers on the malodors of methanthiol and hydrogen sulfide was investigated at room temperature. The experimental results demonstrated that the catalytic activity of such bioactive fibers was tightly correlative to the types of bioactive fibers and substrates.     

STUDY ON THE CATALYTIC ABILITY OF BIOACTIVE FIBERS

1. INTRODUCTIONEnzyme as a biologic catalyst plays an important role in all kinds of chemical reactions inside living creatures. Comparing to chemical catalysts, the natural enzyme has many advantages such as high speed, specificity, sensitivity and mild …     

Influence of the draw ratio on the tensile and fracture behavior of NMMO regenerated silk fibers

The tensile properties and fracture surfaces of N‐methylmorpholine‐N‐oxide (NMMO) regenerated silk fibroin fibers produced with a range of draw ratios has been characterized and related to their microstructure with data obtained from Raman spectroscopy and birefringence measurements. The spinning process allows control of two different draw ratios, coagulation, and postspinning, and it has been found that the microstructure and the properties of the fibers can be modified by the proper combination of both draw ratios. NMMO regenerated silk fibroin fibers subjected to postspinning drawing yield tensile properties comparable to other regenerated fibers and strain at breaking comparable to natural Bombyx mori silk fibers. Tensile strength; however, is still significantly lower than that of natural fibers. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 2568–2579, 2007     

Physicochemical aspects of the liposome-wool interaction in wool dyeing

Despite the promising application of liposomes in wool dyeing, little is known about the mechanism of liposome interactions with the wool fiber and dyestuffs. The kinetics of wool dyeing by two dyes, Acid Green 27 (hydrophobic) and Acid Green 25 (hydrophilic), were compared in three experimental protocols: (1) without liposomes, (2) in the presence of phosphatidylcholine (PC) liposomes, and (3) with wool previously treated with PC liposomes. Physicochemical interactions of liposomes with wool fibers were studied under experimental dyeing conditions with particular interest in the liposome affinity to the fiber surface and changes in the lipid composition of the wool fibers. The results obtained indicate that the presence of liposomes favors the retention of these two dyes in the dyeing bath, this effect being more pronounced in case of the hydrophobic dye. Furthermore, the liposome treatment is accompanied by substantial absorption of PC by wool fibers with simultaneous partial solubilization of their polar lipids (more evident at higher temperatures). This may result in structural modification of the cell membrane complex of wool fibers, which could account for a high level of the dye exhaustion observed at the end of the liposome dyeing process.     

The Identification of Cotton Fibers Dyed with Reactive Dyes for Forensic Purposes

Some of the most common microtraces that are currently collected at crime scenes are fragments of single fibers. The perpetrator leaves them at a crime scene or takes them away, for example, on their clothing or body. In turn, the microscopic dimensions of such traces mean that the perpetrator does not notice them and therefore usually does not take action to remove them. Cotton and polyester fibers dyed by reactive and dispersion dyes, respectively, are very popular within clothing products, and they are hidden among microtraces at the scene of a crime. In our recently published review paper, we summarized the possibilities for the identification of disperse dyes of polyester fibers for forensic purposes. In this review, we are concerned with cotton fibers dyed with reactive dyes. Cotton fibers are natural ones that cannot easily be distinguished on the basis of morphological features. Consequently, their color and consequently the dye composition are often their only characteristics. The presented methods for the identification of reactive dyes could be very interesting not only for forensic laboratories, but also for scientists working in food, cosmetics or pharmaceutical/medical sciences.     

低温等离子体处理天然纤维的ESR研究

低温等离子体表面改质技术,近年来在纤维加工领域的应用引起广泛注目。纤维、高分子材料经低温等离子体处理,在纤维基质中生成自由基。这些自由基同活性原子团一样,其中不稳定的自由基迅速重新结合,而稳定的自由基就残留在纤维基质中。本文研究了天然纤维棉、麻、羊毛和蚕丝分别在O_2、N_2、Ar、CO及CF_4气体中的低温等离子体表面改质处理,用ESR光谱测定了纤维基质中生成的自由基的相对强度,并讨论了热处理对自由基稳定性的影响。     

Synthesis and application of disazo reactive dyes derived from sulfatoethylsulfone pyrazolo[1,5-a]pyrimidine derivatives

Two models of heterocyclic reactive dyes based on disazo pyrazoloprymidine derivatives and possessing a sulfatoethylsulfone reactive group were synthesized and characterized by elemental analysis, IR and ¹H NMR spectroscopy. The dyes were applied to cotton, wool and silk fabrics. Effects of varying dyeing conditions were investigated. The results assessed for the exhaust dyeing methods on the different fabrics indicate that these reactive dyes showed high exhaustion and fixation values. The dyed fabrics also showed very good light fastness and good to excellent washing, rubbing and perspiration fastness.