高温磺甲基化碱木质素染料分散剂的制备及性能

Preparation and Performance of High Temperature Sulfomethylated Alkali Lignin Dye Dispersant

以酸析碱木质素（AL）为原料，通过高温磺甲基化改性反应制备不同磺酸基含量的磺甲基化碱木质素（SAL），研究了各反应工艺条件对产物磺酸基含量的影响，并测定了产物用作染料分散剂的高温稳定性和对纤维的沾污性。通过优化得到以下工艺条件IW（AL）=25．0％，反应温度为180℃，反应时间为4h，反应体系pH=11．0，n（亚硫酸钠）：n（甲醛）=3．5：1。在该工艺条件下，通过调节亚硫酸钠用量制备不同磺酸基含量的SAL。对SAL的性能测定结果表明，SAL磺酸基含量为1．2～1．4mmol／g时具有较优的综合性能，尤其是高温稳定性出色，130℃高温处理后染料分散液的平均粒径最低为14．347μm，明显优于商品染料分散剂UNA（86．125μm）和NNO（59．886μm），但是对纤维还具有一定的沾污性。

Sulfomethylated alkali lignins （SAL）with different sulfonic group content were prepared from acid precipitated alkali lignin（AL） through high temperature sulfomethylation. The influence of reaction conditions on the sulfonic group content of SAL was studied. The high temperature stability and fiber staining were tested. SALs with different sulfonic group content were obtained by adjusting the dosage of Na2SO3 under the optimal modified conditions：the w （AL） was 25.0% , reaction temperature was 180 ℃, reaction time was 4 h, pH of solution was 11.0, and n （ Na2 SO3 ） ： n （ CH2 O） was 3.5 ： 1. SALs with the sulfonic group content of 1.2 ～ 1.4 mmoL/g possess good comprehensive performance, with especially outstanding high temperature stability. The lowest average particle size of dye dispersant after 130℃ treatment is 14. 347 μm, which is far less than those of commercial dye dispersant UNA （86. 125μm） and NNO（59. 886 μm）. However,they introduce some staining to fibers.