Synthesis, Characterization and Application of Some Polymeric Dyes Derived From Monoazo Disperse Dyes

Abstract

In this study, Some Monoazo disperse dyes namely, 4-arylazoaminophenols (AAPs) were synthesized via diazotization and coupling reactions and later, polycondensation of these dyes with formaldehyde in the presence of aqueous oxalic acid was carried out. The resulting polymeric dyes namely, (4-arylazoaminophenol- formaldehyde)s (PAAP-F)s as well as their low-molecular weight precursors were characterized by yield, melting point, color, solubility, viscosimetry, Proton Nuclear Magnetic Resonance spectroscopy, UV-visible spectroscopy and Infra red spectroscopy. Their dyeing performance on nylon and polyester were assessed using standard methods. The products were obtained in good yield and had low melting points The dyes were found to be soluble in chloroform and acetone, some were found to dissolve in ethanol and methanol, and generally insoluble in water. The dyeing on nylon and polyester had yellow shades with moderate to good light and wash fastness. Their rubbing fastnesses on nylon and polyester were very good. Polymerizations of the monomeric dyes on dyed nylon and polyester have also been carried out. The dyeing properties of the monomeric and polymeric dyes were compared with the dyes polymerized in situ on nylon and polyester and the fastness properties were found to increase on polymerization and even better with the dyes polymerized inside the fibers.