2.5%毒死蜱微球悬浮剂的制备

Preparation of 2.5% chlorpyrifos microspheres suspension concentrate

采用流点法对毒死蜱微球悬浮剂的润湿分散剂种类进行了筛选,在所筛选的10种分散剂中,SOPA和N-甲基脂肪酰基牛磺酸盐的流点值较小,分别为0.5032和0.4656.进一步筛选了增稠剂、防冻剂,较优配方:11.2%毒死蜱聚乳酸微球、2.5%SOPA、2.5%N-甲基脂肪酰基牛磺酸盐、3.5%硅酸镁铝、5%乙二醇、0.15%有机硅消泡剂、0.1%苯甲酸钠、水75.05%,制剂的各项质量技术指标基本合格.生测结果表明,2.5%毒死蜱微球悬浮剂对小菜蛾幼虫的毒力略低于48%毒死蜱乳油.

The different wetting dispersants were screened by using pour point method. Among the 10 wetting dispersants, the pour points of SOPA and N-methyl fatty acyltaurine were lower （0.5032 and 0.4656, respectively）. Based on the screening of wetting dispersants, thickening agents and anti-freeze agents were obtained. The formulation included 11.2% chlorpyrifos polylactic acid microspberes, 2.5% SOPA, 2.5% N-methyl fatty acyhaurine, 3.5% magnesium aluminum silicate, 5% ethylene glycol, 0.15% silicone antifoaming agent, 0.1% sodium benzoate and 75.05% H20. The formulation conformed to the requirements for a suspen- sion concentrate in all respects. The LCso values of 2.5% chlorpyrifos microspheres suspension concentrate against Plutella xylosteUa at 48 h was slightly higher than that of 48% chlorpyrifos EC.