Abstract:  To improve the dyeing performance of gardenia yellow on cellulose fibers, we designed and synthesized a series of cellulose fiber cationic modifiers with 3-chloro-2-hydroxypropyl as the active group and quaternary ammonium cation as the cationic group. Then, we introduced quaternary ammonium groups into cellulose fibers by nucleophilic addition reaction, and then dyed the fibers with gardenia dyes to improve the dyeing performance of gardenia yellow dyes.
The molecular structures of quaternary ammonium modifiers with different alkyl chain lengths were characterized by ESI-MS and proton nuclear magnetic resonance. FT-IR and X-ray photoelectron spectroscopy confirmed that quaternary ammonium compounds were successfully grafted onto the cotton fabrics through ether bonds. HPLC-MS was used to detect the binding mode between gardenia yellow dye and modified cotton fabrics.
The absorption peak of methyl bending vibration of quaternary ammonium compounds connected to nitrogen atoms on quaternary ammonium groups at 1,470 cm-1 was analyzed by Fourier infrared spectroscopy and the characteristic peak of binding energy of nitrogen elements at 399 eV was analyzed by X-ray photoelectron spectroscopy. It was confirmed that quaternary ammonium compounds were successfully grafted onto cotton fabrics in the form of ether bonds.
The cotton fabric was cationic treated with modifiers with different alkyl chain lengths, and the modified cotton fabric was dyed with gardenia yellow dye to compare the dyeing K/S values of the modified cotton fabric. The experimental results show that the optimal alkyl chain length of the modifier is 12, with a dye uptake rate of 85.46% and a K/S value of 4.33. This is because the growth of the alkyl chain of the modifier increases the positive charge on the surface of the fabric, enhancing the adsorption of dyes. But at the same time, the growth of the alkyl chain increases the molecular volume of the modifier, resulting in most of the modifier being grafted on the surface of the fiber, hindering the diffusion of dyes into the interior of the fiber. Therefore, when the alkyl chain is 18, the K/S value actually decreases.
The cotton fabric was modified with cationic modifier with the same concentration and different alkyl chain lengths, and the cotton fabric modified with quaternary ammonium cation with different alkyl chain lengths was dyed with gardenia yellow dye. And the effects of dyeing process conditions on K/S value, dyeing rate and color fastness of dyed fabrics were studied. The experimental results show that the dyeing performance of the fabric modified with CH-12 is the best, with a dyeing rate of 88.07% and a K/S value of 4.71.  At the same time, the cotton fabric modified with CH-12 has a soaping and rubbing fastness of over 3 levels, and a light fastness of 2‒3 levels.

Key words: quaternary ammonium salt, cationic modifier, gardenia yellow, modified cotton fabrics, dye

摘要： 为了提升天然植物染料栀子黄在纤维素纤维上的染色性能，设计合成了一系列以3-氯-2-羟丙基为反应基团、季铵盐为阳离子基团的阳离子改性剂，通过亲核加成反应在纤维素纤维上引入季铵基团，提升栀子黄染料对阳离子改性纤维素纤维的染色性能。借助电喷雾电离-串联质谱法（ESI-MS）、核磁共振氢谱（1H NMR）对合成的不同烷基链长的季铵盐改性剂分子结构进行表征。通过红外光谱图和X射线光电子能谱图证实季铵盐化合物以醚键形式成功接枝在棉织物上。采用栀子黄染料对改性棉织物染色，比较不同烷基链长改性剂改性棉织物的染色K/S值发现，改性剂烷基链长为12时最佳，上染率为85.46%，K/S值为4.33。进一步研究染色工艺条件对染色织物K/S值、上染百分率以及色牢度的影响，实验结果表明，在染色温度为80℃，pH值为9，时间为60 min时，经3-氯-2-羟丙基二甲基辛烷氯化铵（CH-12）改性棉织物染色性能最佳，其上染率为88.07%，K/S值为4.71，耐皂洗牢度及耐摩擦色牢度均可达到3级以上。试验结果表明，CH-12改性棉织物可实现无盐染色，且改性织物的上染率、固色率、耐皂洗和耐摩擦牢度均优于未改性织物的传统有盐染色。

关键词: 季铵盐, 阳离子改性剂, 栀子黄, 改性棉织物, 染色