• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2002.04a
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• pp.9-12
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• 2002

The Dyestuff is fixed to the fiber to color it in a unique way depending on the chemistry between them. Whenever there arose problems in coloring fibers, the chemistry of dyestuff could be adjusted to solve them. That manner new concept dye classes, e.g., reactive dyes, disperse dyes, cationic dyes, have arrived along with the introduction of new fibers. The attempt has made to introduce the new reactive dye to solve this problem.

• Bulletin of the Korean Chemical Society
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• v.10 no.4
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• pp.357-359
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• 1989

The ion aggregates formed between cationic triphenylmethane dyes and tetraphenylborate(TPB) or tetrakis(4-fluorophenyl) borate (TFB) anions have been investigated spectroscopically. The photometric sensitivities of the dyes are found to be increasing in the order pararosaniline < malachite green < methyl violet 2B < crystal violet < ethyl violet. Cetyltrimethylammonium bromide(CTAB) and Triton X-100(TX-100) destroy the ion aggregates. By comparing the concentration of surfactant beyond which dye-borate mixed solutions behave identically with the dye blank, the order of hydrophobicity appears to be parallel with that of photometric sensitivity.

• Fibers and Polymers
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• v.5 no.4
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• pp.264-269
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• 2004

The present paper deals with improvement in disperse dyeablility as well as imparting of cationic dyeablility to difficultly dyeable polypropylene by a melt blending technique. Isotactic polypropylene (PP) was blended with fibre grade polybutylene terephthalate (PBT), cationic dyeable polyethylene terephthalate (CDPET) and polystyrene (PS), individually. The resulting binary blends were spun and drawn into fibres at draw ratio 2, 2.5, and 3. The compatibility of blends, structural changes of fibres in terms of X-ray crystallinity, relative crystallinity, sonic modulus, birefringence and thermal stability were examined. The blended fibres were found to be disperse dyeable by the conventional method of high temperature and high pressure dyeing. And this dye ability increased with increase in the level of substitution. PP/CDPET blend also exhibited dyeablility with cationic dyes in addition to that with disperse dyes. The optimum level of blending was predicted keeping in view of tenacity and thermal stability of melt blend fibres. The wash fastness properties of the dyed fibres were found to be of high rate.

• Textile Coloration and Finishing
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• v.24 no.4
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• pp.239-246
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• 2012

The binding isotherms of ionic dyes with Poly(vinylpyrrolidone) in aqueous solution were determined by the dynamic dialysis technique. The shape of the isotherms of cationic dye, C. I. Basic Red 18 with poly(vinlypyrrolidone) showed a partition type. It suggests that the binding involves a non-cooperative mode. Isotherms of an anion dye, a synthesized dye by coupling of diazotized m-trifluoromethylaniline with 2-naphthol-6-sulfonic acid, were sigmoid type and showed multimode interaction. The results were interpreted by the McGhee von Hippel theory. The thermodynamic parameters for the complex formation of the dyes-polymer were calculated from their temperature dependences of the intrinsic binding constant.

• Textile Coloration and Finishing
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• v.9 no.3
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• pp.42-49
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• 1997

In order to study the dyeability of reactive dyes fixable at neutral pH, three reactive dyes(DYE-NC, DYE-PC, and DYE-LC) were prepared by the reaction of Cibacron Brilliant Red 3B-A with nicotinic acid, pyridine, and lutidine, respectively. FT-IR and UV/Vis spectrophometry were used to identify the dyes prepared. While the maximum absorption wavelength (&{\lambda}_{max}&) of Cibacron Brilliant Red 3B-A was 515nm, the &{\lambda}_{max}& of DYE-NC, DYE-PC, and DYE-LC were 522nm, 525nm, and 536nm, respectively. The &{\lambda}_{max}& was shifted to the longer wavelength by introducing the electron donating groups to the pyridine ring of Cibacron Brilliant Red 3B-A. All of the reactive dyes synthesized showed good exhaustion and fixation property to cotton fabric at higher temperature and neutral pH condition. It was regarded that the quaternary pyridinium ion functionated as the leaving group instead of the chloride ion. Among them, DYE-NC showed the best dyeability at the above condition. It was considered that the electron withdrawing carboxylic acid group in nicotinic acid enhanced the cationic property of nitrogn in pyridine ring, resulting the good reactivity with OH group in cellulose.

• Membrane and Water Treatment
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• v.9 no.2
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• pp.87-94
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• 2018

The interactions of water soluble polymers with dye are studied by ultrafiltration using a molecular weight cut off of 10 KDa regenerated cellulose ultrafiltration membrane. Two water-soluble polymers, namely Poly (Sodium-4 Styrenesulfonate) (PSS) and Poly (Vinyl Alcohol) (PVA) were selected for this study. The effects of process parameters, such as, polyelectrolyte concentrations, transmembrane pressure, ionic strength and pH of solution on dye retention and permeation flux were examined. PSS enhanced ultrafiltration achieved dye retention as high as 99% as a result of complexation between polyanion containing aromatic groups and cationic dye. This result was confirmed by the red shift. The retention of dye decreases as the salt concentration increases, a high retention was obtained at pH above 4. However, in case of PVA, relatively low retention (50%) was observed. Ionic strength and pH has no significant effect on the removal of MB. The permeate flux depended slightly on polyelectrolytes concentrations, transmembrane pressure, salt concentration and pH.

• Membrane and Water Treatment
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• v.14 no.3
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• pp.121-128
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• 2023

This study introduces a NaOH/Zn-assisted hydrothermal method for the synthesis of zeolites derived from coal ash (CA). A zeolite/Zn adsorbent is successfully prepared by the activation of CA with NaOH and Zn; it is characterized by a high surface area and a negative surface charge.Methylene blue (MB) and methyl orange (MO) are selected as dye pollutants, and their adsorption onto the zeolite/Zn adsorbent is investigated. Results show the high adsorption capacities of MB and MO and that the negative surface charge facilitates electrostatic interactions between the adsorbates and adsorbents. The zeolite/Zn adsorbents shows the selective adsorption of positively charged dye MB via electrostatic interactions between the =NH+ group (positive dipole) and the oxygen functional group of the adsorbents (negative dipole). The selectivity for the positively charged dye is sufficiently high, with the removal efficiency reaching 99.41% within 10 min. By contrast, the negatively charged dye MO exhibits negligible absorption. These findings confirm the role of electrostatic interactions in the adsorption of MB, in addition to the effect of a large surface area. The results of this study are expected to facilitate the development of simple, eco-friendly, and cost-effective zeolite-based adsorptive composites from CA residuals for the selective removal of dye pollutants from CA waste.

• Carbon letters
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• v.13 no.4
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• pp.212-220
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• 2012

Orange peel (OP) exhibits a sorption capacity towards anionic dyes such as reactive blue 19 (RB19). Cetyltrimethylammonium bromide (CTAB) as a cationic surfactant was used to modify the surface nature of OP to enhance its adsorption capacity for anionic dyes from an aqueous solution. Four adsorbents were investigated: the OP, sodium hydroxide-treated OP (SOP), CTAB-modified OP and CTAB-modified SOP. The physical and chemical properties of these sorbents were determined using nitrogen adsorption at 77 K and by scanning electron microscope and Fourier transform infrared spectroscopy techniques. The adsorption of the RB19 dye was assessed with these sorbents at different solution pH levels and temperatures. The effect of the contact time was considered to determine the order and rate constants of the adsorption process. The adsorption data were analyzed considering the Freundlich, Langmuir, Elovich and Tempkin models. The adsorption of RB19 by the assessed sorbents is of the chemisorption type following pseudo-first-order kinetics. CTAB modification brought about a significant increase in RB19 adsorption, which was ascribed to the grafting of the sorbent with a cationic surfactant.

• Journal of the Korean Chemical Society
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• v.20 no.4
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• pp.270-276
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• 1976

The absorption spectra and the dissociation constants of various sulfophthaleins have been measured in the presence of a cationic surfactant. In the presence of 2.0 ${\times}$ 10-3 M zephiramine and an ionic strength of 0.05 at 25${\pm}1^{\circ}C$ the absorption maxima of the basic forms are shifted to red by 6${\sim}$21 nm and their molar absorptivities are increased, while the absorption maxima of the yellow forms are shifted to blue by 4${\sim}$20 nm and their molar absorptivities are decreased. The decreases in pKa values are of the order of ranging -1.38${\sim}$0.37. The characteristic of the observed changes has been explained by the assumption that the dye molecule adsorbed on micellar surface forms a stable coplanar structure easily and then the conjugation in the dye molecule is elevated.

• Journal of the Korean Chemical Society
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• v.17 no.6
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• pp.411-415
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• 1973

The reaction between cyanide ion and triphenyl methane dyes is subject to marked catalysis by cationic micelles of cetyltrimethyl ammonium bromide(CTABr) and retarded by anionic micelles of sodium lauryl sulfate(NaLS). Added salts, anions inhibit the catalysis by CTABr, and cations, especially $Zn^{++},\;Cd^{++}$ decrease the retardation of the reaction rates in the presence of NaLS. The kinetic effects of the ionic micelles are much larger in water than in ethanol-water, methanol-water, propanol-water and acetone-water, but strange solvent effects, acceleration the reaction rates, was found in the reaction with malachite green in water-methanol system.