Investigation of novel indoline azo disperse dyes: synthesis, DFT simulation, and dyeing performance on PET and PA fabrics

Abstract

The feasibilities of the chemical reactions of indoline were analyzed with density functional theory (DFT) simulation. A series of azo disperse dyes using indoline as a coupling component were synthesized, namely D1–D6. The synthesized dyes were investigated by UV-visible, FT-IR, ¹H-NMR and MS spectroscopies. DFT simulation was applied to analyze the spectrometric properties of designed dyes. The dyeing of polyethylene terephthalate (PET) and nylon (PA) fabrics were assessed and compared. The synthesized indoline azo disperse dyes exhibited a yellow to red hue on the PET and PA fabrics. Deep shades were achieved with increased dye concentrations for D1 and D2 for the PET and PA fabrics. Excellent rubbing fastness and good sublimation fastness were achieved. Interrelations between dye structures and dyeing performance on the PET and PA fabrics were investigated using DFT calculations.