高效氯氰菊酯微乳化复合表面活性剂体系的相行为及增溶

Phase Behavior and Solubilization of Mixed Surfactants for the Microemulsification of Beta-cypermethrin

目的评价阴离子与非离子表面活性剂复配使用在高效氯氰菊酯微乳化形成与稳定中的作用。方法利用微乳液拟三元相图,研究了不同高效氯氰菊酯油-水-复合表面活性剂体系的相行为和最大增溶量。结果采用阴离子表面活性剂农乳500#与非离子表面活性剂农乳400#以1/1、1/2、1/3复配,高效氯氰菊酯微乳剂拟三元相图中单相区和可对水无限稀释区面积均比表面活性剂单用明显增加,复合体系的最大增溶量也显著提高;与农乳400#单用相比,当二者以最佳比例1/2复配使用时,实现相同高效氯氰菊酯与油相质量分数的微乳化,配方中所需最低表面活性剂的质量分数由52.5%下降到11.5%。结论采用阴离子与非离子表面活性剂适当比例复配使用,可以降低农药制剂微乳化表面活性剂的用量、提高农药有效成分含量,从而提高农药微乳剂的质量和市场竞争力。

[Objective] The purpose of this experiment is evaluate the effects of combined use of anionic and nonionic surfactants on the formation and stability of beta-cypermethrion microemulsification. [Method] The phase behavior and the maximum solubilization capacity of different mixed oil-mixed surfactants-water systems were studied in a pseudo-ternary phase diagram. [Result]The results indicated that the isotropic and monophasic area could be diluted with water to nearly 100% area in the phase diagrams and the solubilization capacity of surfactants mixtures increased significantly as the anioic surfactant Nongru 500# and the nonionic surfactant Nongru 400# were composed at the mass radio of 1：1, 1：2 and 1：3. Compared with Nongru 400#, the concentration of combined use of Nongru 500# and Nongru 400# at a suitable mass radio of 1：2 used for the microemulsification to the same phase volume of beta-cypermethrion and oil decreased to 11.5% from 52.5%. [ Conclusion ] It seems that the combination of nonionic surfactant and anioic surfactant at a suitable mass radio is beneficial to the decrease of surfactants dosage and the increase of pesticide active ingredient in the pesticide microemulsion and it will improve the quality of beta-cypermethrion microemulsion and make it more competitive in the market.