黄原胶的碱处理及其在印花中的应用

The alkali modification of xanthan gum and its application in printing

在加热条件下，通过添加不同量的氢氧化钠对黄原胶进行改性处理，研究不同氢氧化钠用量对黄原胶物理性能的影响，并探讨不同改性程度的黄原胶在棉织物活性染料印花中的印制性能．结果表明，随着氢氧化钠用量的增加，改性程度逐渐增大，黄原胶的表观粘度及特性粘度逐渐减小；在棉织物活性染料印花中，与未改，性黄原胶相比，改性黄原胶的透网量和织物表面得色量分别提高30％～50％和32％～57％，当n（氢氧化钠）：n（黄原胶重复结构单元）=0．802：1-1．210：1时，可以印制得色均匀的块面，满足印制要求．

Xanthan gum was modified by adding different amount of sodium hydroxide under heating con- dition. The effects of sodium hydroxide dosage on the physical properties of modified xanthan gum were dis- cussed. In addition, the printing performances of modified xanthan gum on cotton printed with reactive dyes were investigated. The results showed that the modification degree increased while the apparent viscosity and intrinsic viscosity gradually decreased with sodium hydroxide dosage increasing. Compared with the native xan- than gum, the paste add-on and color yield of modified xanthan gum on cotton printed with reactive dyes raised by 30%-50% and 32%-57%, respectively. The uniform color patterns could be achieved to meet the printing requirements when n（sodium hydroxide）＇n（repeated structural unit of xanthan gum）=0.802： 1 N 1.210： 1.