Facile synthesis and dyeing performance of some disperse monomeric and polymeric dyes on nylon and polyester fabrics

S S Abdullahi,R E A Mohammad,S Habibu,H Musa,A H Birniwa

doi:10.4314/bcse.v35i3.2

Abstract

ABSTRACT. Monoazo disperse polymeric dyes consisting of polyarylazocarboxybenzene-formaldehyde (PACB-F) and polyarylazohydroxynaphthalene-formaldehyde (PAHN-F) were synthesized through diazotisation, coupling and polycondensation reactions in the presence of formaldehyde and aqueous oxalic acid. The structure of the as synthesised dyes was acquired using UV-visible absorption maxima and FT-IR spectroscopy and their color, yield, melting point, solubility, and viscosity determined via standard methods. UV-visible and FTIR results showed successful formation of the polymeric dyes due to shift of wavelength of maximum absorption (λmax) (420-470 nm, 460-510 nm) and new absorption peak at around (2800-2995 cm-1) for methylene bridge, respectively. The yield of the monomeric dyes was 67.1-85.7% and polymeric 45.1-59.3%, melting point was 104.1-131.2 oC, and 136.0-143.5 oC, respectively. They are soluble in acetone, ethanol, and methanol and insoluble in n-hexane and water. The dyeing process was achieved via high temperature and carrier dyeing techniques on nylon and polyester fibers. The dyeing characteristics of the synthesised dyes were analyzed in comparison with commercial disperse dyes (terasil brilliant violet and terasil scarlet brown). The dyeing produced a very attractive hue brown shades with good to excellent washing, light, hot pressing, and rubbing fastness.  KEY WORDS: Carbocyclic, Dyeing activity, Monoazo, Monomeric, Polymeric  Bull. Chem. Soc. Ethiop. 2021, 35(3), 485-497. DOI: https://dx.doi.org/10.4314/bcse.v35i3.2

Highlights

The antiquity of synthetic colorants is strongly related to the current progress of theoretical organic chemistry and measured by social and economic influences in the emerging industrial states of the late 19th century [1]
The proposed synthetic steps for the synthesis of polymeric dyes through diazotization, coupling and polycondensation reactions is illustrated in Scheme 1
Polymerization of various carbocyclic monoazo disperse dyes synthesized via diazotisation, coupling, and polycondensation reactions have been achieved

Summary

Introduction

The antiquity of synthetic colorants is strongly related to the current progress of theoretical organic chemistry and measured by social and economic influences in the emerging industrial states of the late 19th century [1]. Comparatives colour fastness properties of the monomeric, polymeric dyes and commercial disperse dyes (terasil brilliant violet and terasil scarlet, brown) on nylon and polyester fibers were assessed and compared according to ASTM standard.

Results

Conclusion