由于生态和经济需求,开发分散的偶氮染料的清洁合成技术对于染料行业至关重要。本研究提出了一种清洁,安全,低能耗的制备基于2,6-二溴-4-硝基苯胺的分散偶氮染料的方法,该方法收率高,反应时间短。从有机反应体系中沉淀出特有的稳定的2,6-二溴-4-硝基苯胺硫酸重氮盐,并将固体重氮盐直接用于合成分散的偶氮染料。与传统方法相比,该方法的硫酸用量减少了80%,废无机盐的用量减少了80.9%,反应系统释放的热量减少了88.5%。染料结构通过1 H NMR验证,1313 C NMR,傅立叶变换红外光谱(FT-IR)和高分辨率质谱(HR-MS)。与市售染料相比,制备的染料具有足以用于工业应用的相同的染色性能。
A new synthetic strategy for industrially important deep-shade disperse azo dyes was presented in this study. The key procedure is to prepare stable solid diazonium salts of weakly basic amines in the absence of concentrated sulfuric acid. Diazotization by tert-butyl nitrite in ethylacetate was allowed to proceed in the presence of equivalent 1,5-naphthalenedisulfonic acid as stabilizer of diazonium