Investigation of Synthesis, Application and Fluorescent Properties of Novel Acid Dyes Based on Perylene on Polyamide Fabrics

Two novel perylene-based acid dyes were synthesized to produce fluorescent polyamide fabrics. The dyes were made by reacting perylene-3,4,9,10-tetracarboxylic acid dianhydride (PTCA) with sulfanilic acid and 1-amino-8-hydroxy-3,6-naphthalene disulfonic acid (H-acid) in imidazole as a solvent. FTIR, 1HNMR, UV–Vis, elemental analysis, and spectro-luminescence were used to characterize the synthesized dyes. Dyes with approximately similar maximum wavelengths had molar absorption coefficients of 42,996 and 8636 l mol−1 cm−1 in water. The dyes showed a negative solvatochromism effect with changing the polarity of solvents from water to methanol. Also, the sulfanilic acid-based dye had a higher quantum efficiency (φ = 0.79) and stokes shift (1999 cm−1) than the H-acid-based dye in water. The DFT method analyzed the synthesized dyes' HOMO, LUMO, bandgap, dihedral angles, and angle of substitution. Both dyes had the same bandgap and dihedral angles. Substituted sulfanilic acid derivative had more planar structure than H-acid derivative. The synthesized molecules were used to dye polyamide fabrics. Dyeing kinetics were based on pseudo-second-order and Langmuir isotherms. Also, the sulfanilic-acid derivative had more build-up on polyamide fabrics. According to fabric fastness tests, synthetic dyes had excellent washing and rubbing stability but weak to moderate light fastness. Finally, the fluorescent properties of dyed fabrics were obtained.