ABSTRACT The aggregation behaviours of three primary reactive dyes in water were determined by molecular dynamics simulations. The aggregation equilibrium time period was determined by SASA analyses. The maximum aggregation sizes for the seven systems were not greater than that of a pentamer. For single dye solutions, the aggregation trend followed the order Y176 > B194 > R239. For two-colour mixed dye solutions, the aggregation compatibilities followed the order Y176-B194 > Y176-R239 > B194-R239. Overall, the three dyes had satisfactory aggregation compatibilities. The dye-dye and dye-water molecule interactions were analysed by RDG and aRDG methods. The results graphically showed the place, strength and type of the interactions. The main interactions between the dye anions were the VdW and π-π stacking interactions. Most parts of the dyes showed VdW interactions with water. The aggregation tendency may be affected by the number and the position of the water-soluble groups of the dyes, the molecular weight of the dye molecules and whether or not the configuration of the dyes was beneficial to the formation of π-π stacking interactions.

中文翻译：

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通过分子动力学模拟研究三种主要活性染料的聚集行为

摘要 通过分子动力学模拟确定了三种主要活性染料在水中的聚集行为。聚集平衡时间段由 SASA 分析确定。七个系统的最大聚合尺寸不大于五聚体的聚合尺寸。对于单一染料溶液，聚集趋势遵循 Y176 > B194 > R239 的顺序。对于双色混合染料溶液，聚集相容性遵循 Y176-B194 > Y176-R239 > B194-R239 的顺序。总体而言，三种染料具有令人满意的聚集相容性。通过RDG和aRDG方法分析染料-染料和染料-水分子相互作用。结果以图形方式显示了相互作用的位置、强度和类型。染料阴离子之间的主要相互作用是 VdW 和 π-π 堆积相互作用。大部分染料显示出与水的 VdW 相互作用。聚集趋势可能受染料水溶性基团的数量和位置、染料分子的分子量以及染料的构型是否有利于形成π-π堆积相互作用的影响。