机械能与界面张力在农药水乳剂制备中的作用机理研究

The Mechanism Research of the Engine Energy and the Surface Tension on Preparation of Pesticide Emulsion in Water

为了探明机械能与界面张力在农药水乳剂制备中的作用机理,配制了6.9%精唑禾草灵水乳剂、30%毒死蜱水乳剂、5.7%氟氯氰菊酯水乳剂,测定、对比了同一配方用不同加工设备得到的乳状液的析水率、乳滴粒径分布以及同一种农药用不同乳化剂组合加工得到的乳状液的析水率、乳液稳定性和界面张力等数据。结果表明:用非离子型乳化剂尤其是相对分子质量较大的、具有嵌段聚醚型结构的非离子型乳化剂和磷酸酯类的阴离子型乳化剂配制,同时用提供机械能较高的高剪切乳化机加工能得到稳定的乳状液。据此得出结论:在水乳剂的配制过程中,选择合适的乳化剂减小界面张力,同时选择合适的加工设备来增加乳液体系的机械能则能快速筛选出优良的水乳剂配方。

In order to explore the mechanism of the engine energy and the surface tension on preparing pesticide emulsions, oil in water, three emulsion in water (EW) formulations, such as 6.9% fenoxaprop-p-ethyl EW, 30% chlorpyrifos EW and 5.7% cyfluthrin EW were carried out. By detecting and comparing the data of the ration of water separation and the particle size (distribution) of emulsion in pesticide prepared by different apparatus, and the data of the ration of water separation, the particle size and the surface tension of the emulsion in pesticide formulated by (different) emulsifiers, we found that stable formulations could be formed by using nonionic pluronic(poloxamer) polyester with a broad molecular weight distribution and high molecular weight phosphate esters (acid form) under rotar-stator stirrer with high engine energy. As a (result), choosing suitable emulsifier to decrease the surface tension and utilizing suitable (apparatus) to increase the engine energy were favorable in preparing good EW formulation smoothly.