Xanthan Gum's Appliccation On Dispersdyestuff Printing On Polyester Fabirc

Xanthan gum is a polysaccharide produced by a biotechnological fermentation process based on corn starch. Nowadays, Xanthan has been bulk produced in European countries and used mainly in the fields of food munufactory, medicine manufactory, petroleum drilling, and other consumer goods industry. It has huge commercial potential.Disperse dyestuff printed polyester fabric is one of the most popular part in the whole printing family. Alginate, starch and acrylic thickeners are common used as printing paste in industry. But for Alginate, the price of raw material is increasing every year and also the source is limited; for synthetic thickeners, they don't have good biodegradation property. And for the starch thickener, they are not easy to be removed from the fabric and will affect the hand feeling. So, optimized printing paste is necessary for the textile industry. Xanthan gum, as an ecological thickening material, is a new development in the textile printing industry. It has the potential advantage to replace Alginate or Synthetic thickener which had showed the disadvantage in usage. But now there were only few papers which working on experimental application of Xanthan are founded, this field is still in the very beginning steps.In this paper, first printing experiments were done with Xanthan gum and as well as other traditional printing paste. From the experiment, compared with the other two printing thickeners, Xanthan can not offer satisfied printing ability. The dye-up-take of Xanthan is very low but it can offer good sharpness and good outline. After the mixture experiment, we found that Xanthan can help Newton liquid like Alginate to increase the viscosity remarkably, but for pseudo plastic liquid like Acrylic thickener, it has less contribution.To find the reason of Xanthan's poor printing ability, a few of rheological factors were measured and discussed. They are viscosity, PVI, flow curve, viscoelasticity, creep and recover. From the experiment, it shows that Xanthan gum is an effective thickener, can offer high viscosity with low concentration. Xanthan gum is a pseudo plastic liquid or shear-thinning material with high yield value, low PVI, strong surface tension.After the research on the rheological property of Xanthan gum, the modification experiment is discussed in both physical and chemical aspects. First, the blends of Xanthan respective with four other thickeners are used in printing paste. From the printing result and the viscosity of the blends, the effects of Xanthan gum to other thickeners are discussed. Xanthan can improve the viscosity of the system in different ways depends on the thickener species. Secondly, different ion types of surface agents are added into Xanthan printing paste. The surface tension and flow behavior are changed with the existence of surface agent. And the penetration ability of Xanthan gum paste into the fabric is also improved. But if the amount of surface agent is too high, the sharpness of out line will be destroyed. At last, the modification of Xanthatn gum is discussed. H₂O₂ was chosen as the oxidation agent for the modification. Because that the reaction process is relative simple and without pollution to the environment. The oxidized Xanthan gum has lower viscosity comparing with the original one at the same concentration. At the same viscosity, the oxidized Xanthan has better flow behavior and improved dye-up-take. Also the oxidized Xanthan gum has more transparent and homogeneous appearance. Without adding ant-moldy agent such as formaldehyde, oxidized Xanthan gum can keep stable for longer time.Although the oxidation can help Xanthan to optimize it's printing property, the research is still on the base and further more work and research are required to continue.