Study on the application of Acacia nilotica natural dye to wool using fluorescence and FT-IR spectroscopy

Abstract

The present study is aimed to exploit the intrinsic fluorescence emission properties of polyphenols of Acacia nilotica natural dye on natural protein fiber wool. Fluorescence measurements were done before and after dyeing experiments. Owing to these phytoconstituents dyed wool samples illustrate interesting fluorescence property with highest values recorded at 445 nm. Durability of fluorescence finish on exposure to ultraviolet radiations and upon washing has been studied and it was proven that dyed wool samples retain interesting fluorescence properties. Rate of fluorescence fading on exposure to UV radiations follows first order kinetics with decay constant of 9.84×10−6 s−1. Results showed adsorption isotherms are best explained by Langmuir type with high regression coefficient value (R2=0.998) and dyed wool fibers have an obvious fluorescent effect in the spectral range 400–470 nm. The effects of different metallic mordants on the fluorescence property of dyed wool have been assessed in order to increase fluorescence finish. Wool-mordant-dye interactions were studied by Fourier transform infrared (FT-IR) spectroscopy.