非离子表面活性剂对有机染料水分散体的稳定化机制研究

On the Mechanism of Colloidal Protection of Aqueous Dispersions of Organic Dye by Nonionic Surfactants

本文对非离子表面活性剂(作为分散剂)对C.I.分散蓝79水分散体的稳定化机制进行了研究.实验对这些分散体的稳定参量(沉降度)、动电性质以及表面活性剂在染料颗粒表面的吸附等温线进行了成功的关联.结果表明非离子表面活性剂对分散体的稳定化必须通过吸附来完成;活性剂吸附层可能对颗粒双电层结构产生影响.存在一个活性剂浓度的最佳值对应活性剂的吸附量极值和分散体的最佳稳定性.

The mechanism of the colloidal protection of aqueous dispersions of C. I. Disperse Blue 79 by nonionic surfactants (as dispersing agents) was studied. A good correlation of the settling parameter, electrokinetic properties and adsorption isotherms of surfactants on the surfaces of the dye particles was obtained with these dispersions. The results show that the stabilization of the dispersions by the surfactants is achived by their adsorption on the dye particles, and an optimum surfactant concentration corresponds to the best stability of the dispersions. It is considered that the adsorption layer might influence the structure of the electric double layer by the so-called squeezing effect.