Li Qing, Lu Run, Liang Yan, Gao Kang, Jiang Huiyu
Hubei Key Laboratory of Biomass Fibers and Eco-Dyeing & Finishing, College of Chemistry and Chemical Engineering, Wuhan Textile University, Wuhan 430200, China.
Jiangsu Engineering Research Center of Textile Dyeing and Printing for Energy Conservation, Discharge Reduction and Cleaner Production, Soochow University, Suzhou 215123, China.
Materials (Basel). 2022 Aug 25;15(17):5849. doi: 10.3390/ma15175849.
The traditional pre-treatment of cotton fabric hardly meets the requirement of low carbon emissions due to its large energy consumption and wastewater discharge. In this study, a low-temperature and near-neutral strategy was designed by establishing a tetraacetylethylenediamine (TAED)-activated sodium percarbonate (SPC) system. First, the effects of SPC concentration, temperature and duration on the whiteness index () and capillary effect of cotton fabrics were investigated. Particularly, excess SPC's ability to create an additional bleaching effect was studied. The optimized activated pre-treatment was compared with the traditional pre-treatment in terms of the bleaching effect and energy consumption. Further, the degradation of morin, which is one of the natural pigments in cotton, was carried out in a homogeneous TAED/SPC system to reveal the bleaching mechanism. Lastly, the application performance of the treated cotton was evaluated by characterizing the dyeability, mechanical properties, morphology, etc. The research results showed that temperature had a significant influence on both the and capillary effect, followed by the SPC concentration and duration. The was positively correlated with the SPC concentration, but excess SPC could not produce an obvious additional effect. The of the fabric increased by 67.6% after the optimized activated bleaching using 10 mmol/L SPC and 15 mmol/L TAED at 70 °C for 30 min. Compared with the traditional process performed at 95 °C for 45 min, the activated process produced approximately 39.3% energy savings. Research on the bleaching mechanism indicated that the reactive species that participated in degrading the morin were the hydroxyl radical and superoxide radical, and the contribution degree of the former was larger than that of the latter. Two degradation components with molecular weights of 180 and 154 were detected using mass spectroscopy. Based on this, the bleaching mechanism of the TAED/SPC system was proposed. Moreover, the fabric after the activated pre-treatment had a suitable dyeability and strength, a lower wax residual and a smoother and cleaner fiber surface. The encouraging results showed that TAED/SPC is a promising bleaching system that is conducive to the sustainable advance of the textile industry.
由于传统棉织物预处理能耗大、废水排放多，难以满足低碳排放要求。本研究通过建立四乙酰乙二胺（TAED）活化过碳酸钠（SPC）体系，设计了一种低温近中性策略。首先，研究了SPC浓度、温度和时间对棉织物白度指数（）和毛效的影响。特别研究了过量SPC产生额外漂白效果的能力。将优化后的活化预处理与传统预处理在漂白效果和能耗方面进行了比较。此外，在均相TAED/SPC体系中对棉织物天然色素之一的桑色素进行降解，以揭示漂白机理。最后，通过表征染色性能、力学性能、形态等对处理后的棉织物应用性能进行了评价。研究结果表明，温度对和毛效影响显著，其次是SPC浓度和时间。与SPC浓度呈正相关，但过量SPC不能产生明显的额外效果。采用10 mmol/L SPC和15 mmol/L TAED在70℃下处理30 min进行优化活化漂白后，织物白度提高了67.6%。与在95℃下处理45 min的传统工艺相比，活化工艺节能约39.3%。漂白机理研究表明，参与降解桑色素的活性物种为羟基自由基和超氧自由基，前者的贡献程度大于后者。采用质谱检测到分子量分别为180和154的两种降解产物。据此，提出了TAED/SPC体系的漂白机理。此外，活化预处理后的织物具有适宜的染色性能和强度，蜡质残留量较低，纤维表面更光滑、更清洁。这些令人鼓舞的结果表明，TAED/SPC是一种有前景的漂白体系，有利于纺织工业的可持续发展。
