【作者】 王晓丽；

【导师】 董川；

【作者基本信息】 山西大学 ， 分析化学， 2014， 硕士

【摘要】 第一章：概述了三苯甲烷类染料的结构分类及其应用,综述了三苯甲烷类染料的氧化降解方法及其降解机理,阐明了论文的研究意义和内容。第二章：以孔雀石绿、碱性品红、灿烂绿、结晶紫四种三苯甲烷类染料为模型染料,采用化学氧化的方法,以过碳酸钠为氧化剂,研究了过碳酸钠对四种染料的降解行为。以降解率为指标,分别考察了降解过程中的影响因素,包括pH、降解时间、氧化剂用量、温度。结果显示：四种染料降解的最佳pH均为11,温度选择室温(25℃),然而降解时间以及氧化剂的用量因染料而异。当降解时间为20min,50mg/L的氧化剂溶液用量为2mL时,四种浓度为10mg/L的染料溶液均显示了较高的降解率,降解率的大小顺序为：孔雀石绿>灿烂绿>碱性品红>结晶紫,说明过碳酸钠适用于三苯甲烷类染料的降解。第三章：分别以上述四种三苯甲烷类染料为研究对象,基于过碳酸钠对四种染料降解过程中紫外可见光谱的变化,探讨了以过碳酸钠对孔雀石绿、碱性品红、灿烂绿、结晶紫四种染料的降解机理。四种三苯甲烷类染料在氧化降解的整个过程中,随着反应的进行染料的共轭链均被破坏,紫外可见光谱的最大吸收峰逐渐消失。共轭链被破坏的同时还伴随着N-去烷基化反应的进行,最大吸收峰处的波长发生蓝移。紫外可见图谱显示不仅原先的吸收峰的消失而且还伴有新的吸收峰的产生,说明降解过程中生成了中间产物。降解的机理可能包括两个主要过程：(1)HOO一进攻中心碳正离子导致其共轭键断裂的反应；(2)N-去烷基化反应。此外,还可能涉及进一步的苯环去除反应和开环反应。第四章：基于Stober法合成了二氧化硅包覆上述四种三苯甲烷染料的微球,通过紫外可见光谱法、红外光谱法、透射电镜进行表征。使用Stober法制备的微球的平均粒径在250nm左右,而且由紫外可见光谱可以推断出二氧化硅的包覆作用提高了染料的耐候性,红外光谱显示二氧化硅已包覆于染料的表面。依据颜料耐酸碱性测定的国标法GB5211.6-85对所合成微球的耐酸碱性进行测定,所合成的微球作为颜料的耐酸碱性较好。分别以所合成的微球作为颜料,水溶性丙烯酸酯乳液为连结料及助剂制得水性油墨,油墨在过碳酸钠溶液中具有良好的褪色性能,能够在40min内完全褪色。更多还原

【Abstract】 Chapter 1:A summary about the classification of the triphenylmethane dyes and their applications are introduced, the recent progress about the oxidative degradation method and mechanism of triphenylmethane dyes are reviewed, too. At last the content and significance of research are clarified.Chapter 2:Malachite green, basic fuchsin, brilliant green and crystal violet are taken as model compounds, and the degradation conditions of four model dyes are studied with the oxidation of sodium percarbonate. The optimal conditions such as pH, temperature, bleaching time and the dosage of oxidant for bleaching process were investigated based on degradation rate. The results showed that the optimum pH is 11, and room temperature is selected as the optimum temperature. However, the degradation time and the dosage of oxidant are varies due to the different structure of dyes. When adding 2mL 50mg/L sodium percarbonate solution to four kinds of 10mg/L dyes solution, respectively, and the degradation time is 20min, their degradation rates are high, The order of degradation rate is:malachite green>brilliant green> basic fuchsin> crystal violet. It is showed that sodium percarbonate is suitable for the degradation of triphenylmethane dyes.Chapter 3:The degradation mechanism of four model compounds are studied by the changes of their UV-visible spectra after adding sodium percarbonate solution, respectively. During the whole process of oxidative degradation, the maximum absorption peak gradually disappeared and whole conjugated chromosphere structure of dyes has been destroyed. At the same time, there is the N-dealkylation reaction which can be characterized by the blue-shift at the maximum absorption peak. Since the intermediates generated during degradation, the original absorption peak disappeared and new absorption peak generated. It inferred that the possible degradation mechanism of four triphenylmethane dyes included two dominant reaction courses:(1)HOO- attack on central carbon reaction;(2)N-dealkylation reaction. In addition, there may involve some further reaction like removal of benzene reactions and open-ring reactions.Chapter 4:The silica-coated triphenylmethane dyes microspheres were synthesized by Stober reaction, and the microspheres are characterized by UV-visible spectroscopy, infrared spectroscopy, and transmission electron microscopy. IR spectra verified that the silica has been coated on the surface of the dyes. TEM showed that the average diameter of microspheres is about 250nm. The weather resistance of microspheres was improved than bare dye molecules. The acid and alkali resistance investigation by GB5211.6-85 method showed that the as-prepared microspheres has good acid and alkali resistance ability. The water-based ink was synthesized by water-soluble acrylic ester emulsion, microspheres and some additives. The ink has a good bleaching performance in the sodium percarbonate solution, and can completely fade within 40 min.更多还原