Aim: The purpose of this paper is to synthesize and characterize two new direct dyes based on chromenes derivatives. Background: The synthesis of carboxyethyl chitosan (CECS) by the reaction of chitosan and acrylic acid via Michael's addition reaction was conducted. Cotton fabrics were treated with CECS to enhance the exhaustion of dye, fastness properties, and antimicrobial activity of dyed fabric. Methods: Chitosan (CS) and acrylic acid were combined in Michael’s addition process to success-fully produce N-carboxyethylchitosan (CECS). Then, the cotton was treated with different concentrations of carboxyethyl chitosan (0.5–5 wt.%) and then dyed by synthesized mono azo and diazo direct dyes based on chromene derivatives. Results and Discussion: The results regarding dyeing and antibacterial activity indicated high-quality dyeing properties, However, direct dyes showed higher exhaustion and fixation values, fast-ness properties, and the colorimetric CIE L*a*b* C*h° data of the dyed cotton fabric. Conclusion: Cotton fabrics treated with carboxyethyl chitosan and dyed with direct dyes were found to have higher antibacterial activity upon a concentration of 2.5 wt.%. In addition, the anti-bacterial activity towards Gram-positive bacteria was reported to be more than Gram-negative bacteria.

中文翻译：

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羧乙基壳聚糖和合成直接染料处理棉织物的无盐染色增强染色性能和抗菌活性

目的：本文的目的是合成并表征两种基于色烯衍生物的新型直接染料。背景：通过迈克尔加成反应，壳聚糖与丙烯酸反应合成了羧乙基壳聚糖（CECS）。棉织物经过CECS处理，可提高染色织物的染料吸尽性、牢度性能和抗菌活性。方法：采用迈克尔加成法将壳聚糖（CS）与丙烯酸结合，成功制备N-羧乙基壳聚糖（CECS）。然后，用不同浓度的羧乙基壳聚糖（0.5-5 wt.%）处理棉花，然后用基于色烯衍生物的合成单偶氮和重氮直接染料进行染色。结果与讨论：染色和抗菌活性的结果显示了高质量的染色性能，然而，直接染料显示出更高的吸尽值和固色值、牢度性能以及比色 CIE L*a*b* C*h° 数据染色的棉织物。结论：经羧乙基壳聚糖处理并用直接染料染色的棉织物在浓度为2.5 wt.%时具有较高的抗菌活性。此外，据报道对革兰氏阳性菌的抗菌活性高于革兰氏阴性菌。