Synthesis And Application Of Dye-Polyether Derivative With Triazine-Based Hydrolysable Bridge Group

As a water-insoluble dye, disperse dyes need to keep the dispersion state with the help of dispersants and other additives. However, a large number of these auxiliary agents are added in the dye commercial process due to their week interaction with the surface of dye particles. After dyeing, all these chemicals enter into drain and result in a large number of colorful wastewater. At the same time, these auxiliary agents also produce solubilization to the dye and reduce the dye utilization. Therefore, developing high efficient dispersants for disperse dyes, especially environment-friendly super-dispersants, has important significance in improving the quality of disperse dyes, the level of textile printing and dyeing industry, and going with the tide of ecological development in textile industry.Based on outstanding performance of hyper-dispersant and structural characteristic of temporarily solubilised disperse dyes, this paper designed and synthesized a class of new dye-polyether derivative which the disperse dye molecular was grafted onto polyether monoamine via a hydrolyzable triazine bridge. The structure of product was deduced and characterized using FT-IR,1HNMR and elemental analysis, which indicated that the obtained dye-polyether derivative was coincided with the designed structure. Its hydrolysis behavior was also discussed, the results showed that this triazine-based dye-polyether derivative could be hydrolyzed under alkaline conditions, and the hydrolysis rate increased with the increasing pH.The dispersion efficiency of the dye-polyether derivative on the parent dye dispersion was investigated and the results indicated that the introduction of dye molecule into the polyether can enhance the affinity to the dye particle and increase the dispersion efficiency. It was showed that the dispersion ability of the dye can be significantly improved by a small amount of derivative, and dye particle diameter of dispersion system decreased with the increasing amount of dispersant. The adsorption isotherms of polyether and dye-polyether derivative onto the dye particles surface showed that the introduction of important anchoring group, disperse dye molecular, the saturated adsorption amount of dye-polyether derivative was higher than the polyether's obviously. This may be that the dye molecular segment and polyoxypropylene segments of dye-polyether derivative can be adsorbed onto the surface of dye particles, while the polyoxyethylene chains extend into the solvent phase by long tails and form larger space repulsion barrier. Thus the dispersion suspension has a good dispersion performance and stability even at the dye to dye-polyether derivative weight ratio of 10:1, which can achieve the same effect as commercial disperse dyes.The dyeing of polyester fabrics was carried out with prepared dye dispersions, and their dyeing performance were studied. The results showed that the uptake rate of disperse dyes and leveling properties of dyed fabrics can be increased while their fastness was at least as good as the fabrics dyed with commercial dye at the same dyeing concentration. However, the COD values and the absorbance of the dyeing effluent were far lower than that of commercial dye because the less amount of dispersant was used and thus less amount of solubilized dye was left in the dye-bath after dyeing, which this reduced the colored water.