Synthesized hydrazones as dispersed dyes for PET fiber: theoretical and experimental approach

Purpose This study aims to prepare two synthesized hydrazones: 4,6-Bis(1-hydrazonoethyl) benzene-1,3-diol and 4,6-Bis(1-(furan-2-ylmethylene) hydrazono)ethyl) benzene-1,3-diol, nominated as Dye I and Dye II, respectively. The theoretically investigated hydrazones were applied as disperse dyes for polyester fabrics under different conditions. Design/methodology/approach The study’s primary objective was to improve dyeing parameters such as temperature, time, pH and shade. The theoretical study was carried out using the Gaussian 09W software package and DFT/B3LYP/6-311++G** level of theory. DFT is used for calculating ground state and global reactivity descriptors to illustrate the dyeing process. Also, the authors studied non-linear optical (NLO) properties of the two dispersed dyes. Findings The results showed that synthetic hydrazone dyes showed promising NLO properties, efficient dyeing and color strength (K/S) on polyester fabrics. A good agreement between theoretical expectations and experimental study was obtained. Depending on the coupler moieties at a shade of 3%, the colored polyester samples showed a range of colors from beige to dark brown. Originality/value Synthetic disperse dyes are outstanding choices for adding a range of stable colors and excellent color strength to polyester fabrics.