初次油水比对高效氯氟氰菊酯微囊悬浮剂理化特性的影响

采用界面聚合法制备了以聚脲树脂为囊材的15%高效氯氟氰菊酯微囊悬浮剂。在制备过程中，以油相质量与初次用水质量相比得到初次油水比，探究了不同初次油水比对高效氯氟氰菊酯微囊悬浮剂理化性质的影响。设定4个不同初次油水比 (R_i) 处理，分别为R_i = 1 : 0.55、1 : 0.69、1 : 0.83和1 : 0.97，通过光学显微镜、扫描电镜、激光粒度分布仪对所制备微囊的形貌进行表征，并测定包覆率与贮藏稳定性。结果显示:当Ri分别为1 : 0.83和1 : 0.97时，所制备的15%高效氯氟氰菊酯微囊悬浮剂成囊质量高，微囊形貌好，微囊包覆率90%以上，粒径3~4 μm (D₉₅)，贮存稳定性合格。本研究可为制备高效氯氟氰菊酯微囊悬浮剂提供参考。

Effect of initial oil-water ratio on physico-chemical properties of lambda-cyhalothrin microcapsule suspension

A 15% lambda-cyhalothrin microcapsule suspension of polyurea resin was prepared as a capsule material by interfacial polymerization. In the preparation of lambda-cyhalothrin microcapsule suspension, the initial oil-water ratio (R_i) was obtained by the quotient of the weight of the oil phase and the weight of the initial water. The effect of the R_i value on the physico-chemical properties of the lambda-cyhalothrin microcapsule suspension was also investigated. Four 15% lambda-cyhalothrin microcapsule suspensions treated with different initial oil-water ratios were prepared. Their R_i values were 1 : 0.55, 1 : 0.69, 1 : 0.83 and 1 : 0.97, respectively. The morphology of the microcapsules was characterized by optical microscope (OM), scanning electron microscope (SEM) and laser particle size analyzer. The encapsulation efficiency and storage stability of each treatment were determined. The experimental results showed that, when the R_i values were 1 : 0.83 and 1 : 0.97, the 15% lambda-cyhalothrin microcapsule suspension had high capsule quality, good microcapsule morphology, and the microcapsule encapsulation efficiency was 90% or higher. The particle sizes were in the range of 3-4 μm (D₉₅), and the storage stability has also be qualified. This study has provided a reference for the preparation of lambda-cyhalothrin microcapsule suspensions.