Study The Effect Of Dispersants On Disperse Dye In Silicone Non-aqueous Media Dyeing System

In the traditional water-base dyeing of polyester fabric,due to the poor dispersibility of disperse dye in water base,though a certain amount of dispersant has been included in commercial disperse dye formulation,a large amount of dispersant need to be used for improving the dyeing effect.Therefore,traditional water-base dyeing system will produce a lot of wastewater.It is an urgent problem for the dyeing industry to control and reduce the consumption of water and other auxiliaries during dyeing.And that is also a difficult problem that the dyeing industry must overcome to go green and environmental protection.The silicone non-aqueous medium is an eco-friendly,non-toxic,and recyclable dyeing medium.A better dyeing effect can be achieved by dyeing polyester fabrics in a silicone non-aqueous medium with the addition of environmentally friendly dye-promoting agents.Meanwhile,silicone non-aqueous medium can reduce the consumption of water and additives such as dispersants.However,as an important component of commercial dyes,dispersants will affect the dyeing effect when commercial dyes are used in silicone non-aqueous medium.To explore the effect of dispersants further systematically on the dyeing performance of disperse dyes in silicone non-aqueous medium,this paper screened three similarly structured and widely used dispersants NNO,dispersant MF and dispersant CNF,and explored the effect of their dosage on disperse dye and the dyeing effect.Meanwhile,the dispersant and dye accelerant were mixed to explore their influence on the dyeing effect.Finally,in order to illustrate the effect of dispersant and dye accelerant,the dyeing mechanism of disperse dyes in silicon-based non-aqueous medium was studied by LC/MS and XPS and other methods to study the composition of fabric surface color spots.In this paper,three kinds of dispersants were added into the silicone non-aqueous medium to dye polyester fabrics.Dispersant NNO can improve the dye uptake and K/S value of dyed fabric,while the dispersant MF and dispersant would make the dyeing effect worse.Through the analysis of the dispersants structure,the hydrophobic constant Clog P of the dispersant NNO was lower.Meanwhile,the hydrophobic constant and dye uptake rate of other additives were compared,it is found that compounds with a lower hydrophobic constant CLogP can improve the dyeing effect.When the dispersant and dye accelerator were added into the silicone non-aqueous medium,as the number of dispersant increases,more color spots will be produced on the surface of the fabric,and the dye uptake rate and K/S value of the disperse dye decreased.SEM test indicated that there were many agglomerates between the fiber surface.HPLC,LC/MS and XPS tests indicated that the agglomerates on the surface of the fabric were water-soluble.HPLC test showed that the main components of color spots were dispersant,disperse dyes and impurities in disperse dyes,and the content of dispersant reached more than 96%.The LC/MS test showed that the two peaks detected by HPLC at 540nm were a small amount of incompletely reacted intermediate substances[M₂+H]⁺that contained in the disperse dye filter cake and disperse dye[M₁+H]⁺.The intermediate material has a hydrophilic structure and will be sticked on the surface of the fabric under the effect of the accelerant.The XPS test proved that there were a lot of Na and C on the surface of the fabric,and a higher Na content was detected in the samples added with the dye accelerator and dispersant MF,which was also consistent with the staining rate of the dispersant and the content of dispersant in the color spot,indicating that the dispersant MF had the highest staining rate on the fabric.The color spots on the fabric surface were due to that the disperse dye was dispersed in the dye accelerator under the effect of the dispersant,and the agglomerates of the dispersant and the disperse dye cannot be dissolved in the silicon-based non-aqueous medium for a less amount of accelerant.The agglomerates gradually sticked on the surface of the fiber,and finally formed color spots on the surface of the fabric during the dyeing process.This paper revealed that the effect of dispersant on disperse dye and the dye mechanism in the silicone non-aqueous medium,which is helpful to promote the research progress and expansion the research on the field of disperse dye accelerant in the silicone non-aqueous medium dyeing system.This research also paves the way for the further construction of accelerants for the study of the dyeing law of disperse dye.Meanwhile,the research on polyester dyeing in silicone non-aqueous medium further promoted the application process of new dyeing methods,and meets the needs of related industries to achieve green and eco-friendly dyeing.