Dyeing Of Polyester Research Articles

Dermatological Symptoms among Polyester Dyeing and Printing Workers in Mumbai.

Textile is one of the important sectors in the Indian economy. The use of synthetic chemicals is maximum during the wet processing technique, which consists of dyeing, printing and finishing. This study was conducted to find out the prevalence of occupational dermatological symptoms among the workers employed in the dyeing and printing unit of the textile industry. A cross-sectional study, with a sample of 242 workers, was conducted in three different dyeing and printing factories. The workers were interviewed using a semi-structured questionnaire adapted from the Nordic Occupational Skin Questionnaire. The prevalence of dermatological symptoms on the hands was found to be 51.7%. The various pattern of lesions included redness in 0.4% to itching in 26% of dyeing and printing workers. Those working for >5 years had 2.21 times higher risk as compared to those working for ≤5 years Odds Ratio (OR): 2.21; 95% Confidence Interval (CI): 1.19-4.11). Similarly, those working in the dyeing section were at 2.94 times higher risk as compared to those working in the printing section (OR: 2.94; 95% CI: 1.58-5.47). The workers working in the printing and dyeing industry were at risk of developing skin lesions, which can partly be attributed to reactive chemicals used and partly to poor handling practices of the workers.

Experimental Studies on the Phase Separation Behavior of Molten Benzenesulfonate-Modified PET/PA6 Blends

In this work, nylon 6 (PA6) and cationic dyeable polyester (CDP) modified with benzenesulfonate groups were reactively blended in a twin-screw extruder. The well-mixed CDP/PA6 blends were re-molten and statically kept for various amounts of time. The morphology evolution caused by phase separation was observed by a scanning electron microscope (SEM) and an atomic force microscopy-infrared (AFM-IR) technique. In the absence of shear force, the homogeneously mixed blends were found to separate rapidly into two phases because of the poor miscibility between polyester and polyamide. In the early stage, the dispersed phase was small in size and irregular in shape. With prolongation of the phase separation time, the dispersed phase turned into larger and spherical particles to minimize the interface between phases. The phase separation process typically lasted 2 to 7 min. This means that the effects of phase separation on the morphology of the blends cannot be ignored in injection molding, compression molding, or other processing processes short of shear force. The effects of the ratio between polyester and polyamide, the benzenesulfonate content, and the molecular weight of polymers on phase separation behavior were investigated.

Special color change mechanism of Disperse Red 60 in alkaline dyeing system

Color Intex (C.I.) Disperse Red 60 is a bright red anthraquinone dye, but it is easy to produce dyeing defects (a kind of discoloration phenomenon, the partial color is random blue patches) in the polyester dyeing process, and the mechanism of blue patches is unknown, resulting in a low right-one-time of dyeing. To investigate the mechanism of this particular color change, the interaction between C.I. Disperse Red 60 and borax was investigated by absorbance, and samples with blue patches were prepared; the presence of B-N bonds was confirmed by testing the X-ray Photoelectron Spectroscopy (XPS) of the dyed samples. The functional additive LV200 (a polymer containing polyester and polyether) was selected to control the interaction between the Disperse Red 60 and LV200. The results showed the co-existence of the red component (1-amino-2-phenoxy-4-hydroxy-9,10-anthraquinone) and the blue component (1-amino-2-phenoxy-10-hydroxy-4,9-anthraquinone) of Disperse Red 60 was the main reason for the random blue patches (dye defects) during the dyeing process of C.I. Disperse Red 60. By using the functional auxiliary LV200 and the H-bonding of the polar group of the dye, the conversion of the red and blue components of the reciprocal isomers can be controlled, and both bright red polyester-dyed fabrics and purplish red polyester-dyed fabrics can be produced. This provides a theoretical guide to improving the dyeing authentic rate of C.I. Disperse Red 60.

Immobilization of chalcone chemosensor into plasma-pretreated recycled polyester fibers toward multi-stimuli responsive textiles for detection of ammonia

Polyester fibers were applied in different fields, including automotives, plastic furniture, packaging, and medical devices. This can be attributed to its low-cost, good resistant to moisture and chemicals, good resistance to electricity and fatigue, easily repaired from damages, fade-resistant, high flexural and impact strength, and easy manufacturability. However, polyester fibers are inherently stain resistant as they have no active dye sites. Thus, it is impossible to dye polyester after extrusion. Herein, we report the development of novel strategy to produce multichromic polyester textiles by plasma-assisted dyeing with novel chalcone chemosensor disperse dyestuff. Thin layer of chalcone probe was incorporated onto the polyester fiber surface after plasma activation, which creates active dye sites on the fiber surface. Novel hydrazonotriazole chemosensor was synthesized by reflux a mixture of 1, 2, 3-triazole and hydrazine derivatives. Hydrochloric acid was employed as a catalytic agent, whereas absolute ethanol was used as a solvent. Various methods were utilized to prove the structure of the synthesized chemosensor, including Nuclear Magnetic Resonance (NMR), Fourier transform infrared spectroscopy (FTIR) and elemental analysis. The findings indicated that the hydrazonotriazole-dyed polyester (HPET) fibers exhibited satisfactory colorfastness properties, UV protection and antimicrobial properties. Additionally, the dyed polyester fibers demonstrated high importance to build up portable device for onsite colorimetric determination of gaseous and aqueous ammonia, which has been able to cause damages to man organs and even death. The hydrazone group can selectively detect ammonia over other alkaline substances. The limit of detection of the dyed polyester fibers ranged between 5 and 150 ppb of aqueous ammonia, displaying a color switch from yellow (435 nm) to blue (584 nm) as proved by CIE Lab parameters, absorption spectra and color strength (K/S). The dye particle exhibited diameters in the range of 33–86 nm, whereas polyester fibers exhibited a fiber diameter of 75–125 μm, indicating high porosity and large surface area.

Optimal process conditions to recycled polyester dyeing using natural annatto dye

The growing interest in replacing synthetic dyes with natural sources is a result of environmental concern, since natural dyes are less aggressive and more biodegradable. Despite being a sustainable alternative, natural dyes have some limitations. In this context, this paper evaluates the natural annatto dye application in conventional (PES) and recycled polyester (rPES) fabrics, with a view to industrial application. For this purpose, operational parameters (temperature and pH) were varied to achieve the optimum dyeing process condition, regarding the color and quality of fabrics. The temperature oscillated from 98.3 °C to 136.2 °C, while the pH from 4.17 to 9.83 in the liquid bath during dyeing, at a fixed concentration of 1.5% of natural annatto dye, for 60 min. FTIR analysis was performed to characterize the presence of the dye molecule in the dye bath. The dyeing that showed the best results, for the exhaustion (95.6%), KS (2.21) and fastness scores (4/5), was carried out at 115 °C and pH 4.17. The dyed samples showed low light fastness values after 5 h of exposure. Further analysis to show the effect of dyeing time, presented that in 10 min the maximum fabric coloring is reached, with a KS value of 3.58. Also, the color parameters changes of the dye in water solution were evaluated at different pH values. In conclusion, the conditions evaluated for natural annatto dye application presented good dyeability for both fabrics (PES and rPES), demonstrating great potential for use in the textile industry.

Synthesis of novel, coumarin-based, mosquito repellent-cum-multifunctional azo disperse dye for functional dyeing of polyester

With the modernisation in the textile industry, the demand for healthcare and protective textiles is rising. Mosquito repellent, antibacterial, and UV-protective textiles are some of the progressive fields of protective clothing. In the present work, a novel disperse dye was synthesised and applied to the polyester fabric to impart mosquito repellent, antibacterial, and UV-protective functionalities. 2-methoxy-5-nitroaniline was diazotised and reacted with 4-hydroxy coumarin to form an azo dye. The structural and chemical analyses of dye were performed using characterisations, such as Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance (1H NMR), matrix-assisted laser desorption ionisation mass spectrometry (MALDI-MS), CHN analyser, and UV-visible spectroscopy. The prepared dye and dyed fabric were evaluated for photoluminescence properties. As fastness and durability of properties always remain the main issues in dyeing, assessment of fastness of the dyed fabric against laundering was also performed using standard methods. After the dyeing process, the mosquito repellent efficacy of dyed fabric was measured against Anopheles Stephensi. Antibacterial and UV protection adequacies of dyed fabric were assessed using standard methods. Colour strength and colour values also validated the dyeing of samples. The results confirmed the suitability of synthesised disperse dye to impart colour, mosquito repellency (100%), antibacterial activity (>94%), and UV protection to polyester fabrics.

Effect of Various Parameters on Dyeing of Polyester, Cotton and Polyester/Cotton Blend with vat dye

Effect of Various Parameters on Dyeing of Polyester, Cotton and Polyester/Cotton Blend with vat dye

Glutamic acid-glucose Gemini surfactants: physico-chemical properties and effect on the dyeability of polyester fabric

Abstract In this study we used glutamic acid as a linking group and glucose, propylene glycol, and fatty alcohols as raw materials to prepare glutamic acid-glucose Gemini surfactants. Fourier transform infrared spectroscopy was used to verify the structures of the surfactants. We investigated their surface properties (surface tension, contact angles), and their effect on the fluorescence of pyrene. To test their potential application, we prepared emulsions with the surfactants and olive oil, and evaluated the emulsion stability with a particle size analyzer. We also investigated the ability to dye polyester fabrics in the presence of the glutamic acid-glucose-gemini surfactants. Among our synthesized materials, those with shorter alkyl chains exhibited better surface activities and emulsification properties, resulting in excellent dye uptake and leveling.

Distribution mechanism of disperse dyes with similar substituents in a waterless dyeing system based on molecular dynamic simulation

In this paper, starting from the dye molecular structure activity relationship, the effect of substituents on the coloration process, such as dissolution, adsorption and diffusion behaviors, was investigated by molecular dynamics simulations in a waterless dyeing (D5) system. Related dyeing experiment test were performed to verify the accuracy of the simulation results. The results showed that the diffusion coefficient of disperse dyes decreased gradually due to an introduction of one ortho-substituent cyano group compared with unsubstituted dyes. Meanwhile, using the substituent N-cyanoethyl group instead of N-ethyl group in coupling component further decreased the diffusion coefficient, which was attributed to an increase of aggregation capacity. Simultaneously, the solubility of disperse dyes containing bis N-cyanoethyl groups in D5 media also decreased obviously due to the low dye-D5 interaction energy, which was consistent with their aggregation behavior. Additionally, the growing strong interaction energy between dye molecules and polyester fibers due to an introduction of cyano group or N-cyanoethyl group contributed to increasing the adsorption efficiency and dyeing uptake. It will be an effective and labor-saving method to select and develop the special disperse dyes for the sustainable D5 dyeing system.

A review on reverse micellar approach for natural fiber dyeing

AbstractThis study reviews the need and importance of non‐aqueous dyeing systems in the chemical processing industry, especially using the reverse micellar system in the dyeing of natural fibres. When it comes to conventional dyeing systems, which use large quantities of water, chemical, and energy, cause a lot of effluent load to the environment. Again the effluent water has to be treated well to eliminate all the harmful substances in it. To overcome the issues, a lot of research has been carried out in this area to minimise the use of water and chemicals in the dyeing process. Like use of low material to liquor ratio (M:L) in dyeing, dyes with high fixation at lower temperatures, low/salt less dyeing in case of reactive dyeing with cotton, cottonseed oil dyeing, microwave‐assisted dyeing, and use of supercritical carbon dioxide in case of polyester dyeing and many more. All the above said methods are aqueous‐based and, after the completion of dyeing, results in wastewater generation, which requires further treatment to reduce the harmful chemicals. Therefore, to further minimise the use of water and chemicals in the dyeing of natural fibres reverse micellar system has been introduced with the help of surfactants of both Ionic and nonionic in nature. As of today, a lot of work has been carried out in the dyeing of natural fibres with this system by employing ionic, nonionic, and mixed surfactants. Fascinating results were obtained in the dyeing with good levelness, high exhaustion, and fixation values, and results were compared with conventional dyeing. Computer colour matching studies were also done better to understand the applicability of these systems in the industry and found nearer results.

Novel carboxylate comb‐like dispersant used in disperse dyes

AbstractDisperse dyes are insoluble in water, dispersants must be added when dyeing polyester fabrics. Copolymers prepared from styrene (St), acrylic acid (AA), and maleic anhydride (MA) have been used in various fields because of their good amphiphilic properties. In order to obtain a novel dispersant to improve the dispersion property of disperse dyes, St‐AA‐MA copolymer was prepared under certain reaction conditions. Carboxylate comb‐like copolymer(St‐AA‐MA‐PEG) was then synthesized by esterification of St‐AA‐MA with polyethylene glycol (PEG) of different number‐average molecular weights. The structure and properties of St‐AA‐MA and St‐AA‐MA‐PEG were detected and characterized. The effects of length of branch chain and grinding conditions on dispersant properties were also discussed. When PEG600 was used as the branched chain of dispersant, the average particle size of the disperse dye was 256.2 nm, which was smaller than that of the commercial one after grinding. And the zeta potential of the dyestuff using St‐AA‐MA‐PEG600 as dispersant arrived at −41.5 mV. Moreover, the synthesis process of St‐AA‐MA‐PEG is very simple. The resulted sample reveals good dispersion effect for disperse dye. Disperse dye particles featured with small size and concentrated distribution are easy to dye polyester fabrics with suitable dyeing rate. Therefore, St‐AA‐MA‐PEG is an efficient dispersant for disperse dyes.

Ecological Dyeing Technology of Polyester Fabric Using Glycerol

Abstract Textile industry struggles with hazardous industrial effluents, water, and energy consumption for sustainability. In the present study, nontoxic glycerol was used as a dispersing agent with water in order to reduce the chemical consumption and eliminate the use of more water in polyester (polyethylene terephthalate [PET]) dyeing. Glycerol was added to dyeing bath at different concentrations, and disperse dyes were dispersed with using microwave radiation. PET fabric samples were dyed with glycerol using microwave radiation, and dyeing properties were compared with carrier dyeing method. After the dyeing process, spectrophotometric analysis, light, rubbing, and washing fastness of samples were analyzed. The experimental results show that glycerol is an ecological and organic substitution to carrier in PET dyeing. As a result, negative environmental impacts of the traditional PET dyeing method can be reduced using glycerol. Compared with traditional dyeing methods, dyeing with glycerol is a promising alternative for sustainability of the textile industry. Moreover, microwave radiation led to an increase in dye uptake, dyeing rate acceleration, energy, and time saving.

Absorption kinetics and thermodynamics of cationic dyeing for poly(ethylene terephthalate) copolyester modified by 2,2-dimethyl-1,3-propylene glycol (NPG)

The copoly(ethylene terephthalate) (ENCDP) were successfully prepared with 2,2-sodium-5-sulfo-bis-(hydroxyethyl)-isophthalate (SIPE), poly(ethylene glycol) (PEG) and 2,2-dimethyl-1,3-propylene glycol (NPG), named as cationic dyeable polyester. The dyeing properties consisted of adsorption kinetics and thermodynamics of cationic blue X-BL on the ENCDP fabric were investigated. The T-Vickerstaff hyperbolic adsorption model could be used to explain the adsorption kinetics and predict the equilibrium rate constant k, equilibrium dye sorption capacity (C∞), the half dyeing time (t1/2) and diffusion coefficient (D) at different temperatures. According to the adsorption activation energy (Ea)> 40KJ/mol, it is judged that the isotherm adsorption conforms to the langmuir isotherm and possessed the higher correlation. Moreover, the determined thermodynamic parameters including the positive value of adsorption affinity (-Δµ°) and enthalpy change (ΔH°) showed that the dye adsorption onto ENCDP was a chemisorption process of spontaneous and endothermic.

Relationship between Structure and Dyeing Properties of Disperse Dyes in D5 Medium

In this paper, two disperse dyes with different substituents were selected to dye polyester fabrics in decmethylcyclopentasiloxane (D5) medium. The structures and dyeing performance of the two dyes were studied and compared. The results showed that dyes with lower solubility in D5 medium had higher dyeing rates. DFT calculations showed that large steric hindrance of cyano groups on diazo components contributed to improving the dyeing rate. This was due to the generation of more monomolecular dyes by destroying π-π stacking interactions. These results provide theoretical guidance for improving the exhaustion and further promote the industrial development of disperse dye in a D5 dyeing system.

Extraction of Cyclic Oligomer and Their Influence on Polyester Dyeing in a Silicone Waterless Dyeing System.

As a promising new dyeing process without using water, the non-aqueous medium dyeing of polyester has attracted people’s attention and some progress has been made in related research. However, the oligomers of polyester fiber can affect the dyeing of polyester during the use of a silicone waterless dyeing system. Based on this point, the oligomer problem in the silicone waterless dyeing system was investigated. The oligomers of some different types of polyester were extracted by solvent extraction. A treatment method with little influence on the fiber was used to reduce the oligomer content in polyester. The improvement of the dyeing effect of polyester after treatment in silicone medium was studied, and the influence of the oligomer on polyester dyeing was also analyzed. For the dyeing of disperse blue 366, the dye exhaustion was increased by 3.25–3.71%, and the color depth of the dyed sample was increased by 6–13%. Moreover, the colorfastness to rubbing was also improved. In the comparison, the changes in thermal properties and crystallization properties of polyester were tested by differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), and X-ray diffraction analysis (XRD). The results showed that the thermal and crystalline properties of polyester fiber were not changed before and after solvent extraction.

Influence of multi-component composition of dyeing bath in the membrane distillation performance

The influence of the multi-component composition of cotton and polyester dyeing baths was investigated in a DCMD process using a PTFE membrane, aiming to water reclamation from textile wastewater. The process was evaluated with each auxiliary, solutions combining auxiliary and dye, and residual water from pilot-scale dyeing baths. The salts used in the cotton dyeing bath did not influence the DCMD process, resulting in a similar rejection rate and permeate flux to those in dye solutions. The formic acid employed in the polyester dyeing bath resulted in high permeate fluxes but decreased the permeate quality by almost 33%. The surfactants (detergent and dispersant) demonstrated the most harmful behavior in the process, evidenced by a complete membrane wetting. An absence of synergy of the dyes and auxiliaries influencing the DCMD process was verified for the textile dyeing wastewater. This work enabled identifying the influence of each dyeing bath component in the rejection rate and permeate flux, allowing to find alternatives in mitigating the remaining gaps involving DCMD operation and the MD membranes. This work contributes to consolidating this promising technique in water reclamation from textile wastewater, encouraging research on membrane development and modification or integrated operations involving MD.

One-bath one-step dyeing of polyester/cotton (PC) blends fabric with disperse dyes after acetylation of cotton

Aiming at the classic problem of dyeing of polyester–cotton blended fabric one-bath one-step dyeing of PC blends with disperse dye after surface modification of cotton were studied. Surface modification of cotton was carried out using fibrous acetylation methods. The optimum value for surface modification was obtained with a concentration of acetylation agent 16% and time of reaction 2.5 h, gave a percent acetylation of 34. Surface chemistry and thermal decomposition were studied by using FTIR spectra and TGA. The tear strength crease recovery, pilling and abrasion resistance were evaluated. The experiment result of dyeing showed that the optimum value was obtained with dye concentration above 1% at a temperature of 120 °C warp tensile strength decreased by 12% and weft tensile strength was decreased by 9% from the control half-bleached fabric. Results of this study showed that one-step one bath dyed modified PC blend with disperse dye fabric presents good fastness property and color strength values compared with conventional two-bath dyed fabric.

Effect of different filters on the extraction of norbixin from Bixa orellana for synthetic fiber dyeing and development of a post-dyeing process for removal of the unfixed dye

The aim of this study was to compare the efficiency of three types of filters for the extraction of the annatto dye from Bixa orellana for polyester dyeing. In addition, post-dyeing washing processes were proposed to improve the wash and rubbing fastness. In the extraction procedure the paper filter presented the highest yield (13.3%), followed by the polypropylene (11.4%), but there was no significant difference in the results for the exhaustion percentage (average of 87.4%) and K/S values (1.68 to 2.24). Results showed the polypropylene filter was the most suitable and can be reused. The post-dyeing washing processes with detergent improved the fastness increasing the color transfer score from 1.5 (large change) to 3 (small change). An acceptable color difference between the dyed fabric samples before and after washing was observed. Results indicate that the post-dyeing washing process improves the quality of dyed fabrics to levels acceptable for industrial application.

Synthesis of novel bisazo disperse dyes: Spectroscopic characterization, DFT study and dyeing of polyester

A series of bis azo disperse dyes were synthesized starting from benzidine and four couplers contain active methylene group, namely; thiobarbituric acid, barbituric acid, dimedone and thiohydantoin, to give 3 a-c and 4, respectively. The dye products were identified by UV–visible, FT-IR, 1H NMR and 13C NMR spectroscopy. The electronic absorptions of the synthesized dyes indicated that the λmax are slightly dependent on the coupler moieties and quite sensitive to pH change. Dyeing of polyester yarn(PE-Y) was done in DMF, whereas, polyester fabric (PE-F) was dyed in water using dispersing agent DYEWELL-002. Fastness properties of bis azo dyes 3a-c and 4 on PE-F are better than those of PE-Y. The summation of color strength (K/Ssum) values of PE-F followed the order 3c > 4 > 3a >3b. The DFT method was used to calculate the chemical descriptor parameters of the protonated form of bis azo dyes 3a-c and 4, using B3LYP/6-31G(d,p) level for investigation of dyeing efficiencies as well as to predict the mechanism of dyeing process. The computed results point out that dye 3a has the highest dyeing strength based on EHOMO, ELUMO, ΔE, η and S parameters while dye 4 is the highest depending on χ and μ eV parameters. The correlation results of the computed parameter with color strength (K/S) and Exhaustion (%E) in case of PE-Y indicated that they depend mainly on the effect of electronegativity χ with correlation coefficient 0.993 and 0.877, respectively. In a similar way, the PE-F exhibits very good effect of color strength with dipole moment (R2 = 0.899). The protonated dyes 3a-c and 4 can adsorbed on the PE surface either by hydrogen bond or/and electrostatic attraction.

Molecular and excited state properties of photostable anthraquinone red and violet dyes for hydrophobic fibers

The molecular, spectroscopic, and excited state properties of synthetic dyes for fiber-based outdoor materials continue to be of commercial interest. Early developments in this area were reported in the 1980s, when the need for dyes for polyester (PET)-based automobile interiors gave rise to commercially viable nitrodiphenylamine yellow, anthraquinone red and blue, and azo red dyes. To augment that initial knowledge base, the present study involved the use of experimental and theoretical methods to help establish the molecular structures and excited state properties of some more recent dyes for producing photostable colors on PET fibers. Having completed the characterization of present-day scarlet, blue, and yellow disperse dyes for PET-based fibers used outdoors, our attention turned to commercially available red and violet dyes. In this regard, HPLC analysis showed that the red product was a mixture containing four components, while the violet product contained only one component. Results from 1H NMR, HRMS, and single crystal X-ray diffraction analyses indicated that the principal components were dyes having a 1-amino-4-hydroxyanthraquinone base structure. The presence of an –OH group alpha to an anthraquinone C=O moiety provides for intramolecular H-bonding and a subsequent opportunity for intramolecular proton transfer in the excited state – as a photostabilizing mechanism. Further, for both dyes, results from the analysis of Frontier HOMO and LUMO isosurfaces indicated strong HOMO-LUMO overlap without molecular gaps and were consistent with strong excited state energy dissipation in a non-destructive way.