Turbiscan Lab分散稳定性分析仪研究异丙甲草胺水乳剂物理稳定性
Study on the physical stability of metolachlor emulsionoil in water by Turbiscan Lab analyzer

为获得不同因素对异丙甲草胺水乳剂物理稳定性的影响规律,同时验证Turbiscan Lab分散稳定性分析仪预测和评价水乳剂物理稳定性的可行性,利用Turbiscan Lab分散稳定性分析仪,结合加速试验[(54±2) ℃, 14 d]结果,研究了乳化剂用量、体系pH和电解质离子等对磷酸酯盐稳定的异丙甲草胺水乳剂物理稳定性的影响。结果表明:乳化剂三苯乙烯基苯酚聚氧乙烯醚磷酸酯三乙醇胺盐(SCP)用量为6.0%(质量分数)时,水乳剂稳定性最好;过酸或过碱均会破坏水乳剂的稳定性,pH=9时水乳剂可获得较好的稳定性;Mg2+压缩油水界面双电层,导致水乳剂稳定性下降,且Mg2+添加浓度越大,水乳剂越不稳定。Turbiscan Lab分散稳定性分析仪以多重光散射为技术核心,在不破坏样品的前提下,能够准确测定乳状液中浮油、沉淀和液滴粒径大小的变化情况,与加速试验结果吻合度高,不仅能够缩短试验周期,而且可以分析不稳定现象发生的机理。
To study the influence of different factors on the physical stability of emulsion oil in water and verify the feasibility of analyzing and predicting the physical stability of emulsion oil in water by Turbiscan Lab analyzer,the physical stability of metolachlor emulsion in water under different factors such as the dosages of emulsifier,the pH value of the system and the electrolyte ions were investigated by using Turbiscan Lab analyzer combined with the results from acceleration test [(54±2) ℃,14 d].The results showed that:the emulsion stability was the best when the dosage of the emulsifier SCP (polyethylene glycol 2,4,6-tristyrylphenyl ether phosphate triethanolamine salt) was 6.0% (mass fraction);the emulsion stability were destroyed under strong acid or alkali conditions, while it could obtain better stability under pH=9; The decrease of the emulsion stability was caused by the double electrical layer compression at the oil-water interface by Mg2+,and the greater the concentration of Mg2+ was,the more unstable the emulsion was.Turbiscan Lab analyzer is based on the multiple light scattering technique,which could be used to accurately determine the change of the floating oil layer,sedimentation and droplets diameter without destroying the sample.It can not only shorten the test cycle,but also analyze the mechanisms of the instability phenomenon.