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[目的]考察聚乙烯醇和海藻酸钠的添加对微囊悬浮液物理稳定性的影响和相应流变性的变化。[方法]通过界面聚合法制备高效氯氟氰菊酯微囊悬浮液,利用Turbiscan LAB多重光散射稳定性分析仪分析样品物理稳定性,Discovery HR-2型流变仪考察样品流变性。[结果]同一体系下,表观黏度及黏弹性越高,样品越稳定,2.5%聚乙烯醇和0.3%海藻酸钠质量分数样品6 h后的稳定性动力学指数从15.75分别降到了4.00和3.08,且趋于稳定。在低剪切速率下,2.5%质量分数聚乙烯醇样品的表观黏度从8.55×10~(-3)Pa·s提高到71.89 Pa·s,0.3%质量分数海藻酸钠样品表观黏度提高到28.19 Pa·s;在低扫描频率下,2.5%质量分数聚乙烯醇样品的弹性模量从0.03 Pa提高到12.75 Pa,0.3%质量分数海藻酸钠样品提高到3.96 Pa。[结论]适量地添加高分子聚合物可改变样品的空间效应,从而可改变其流变行为,并使其物理稳定性提高。
[Objective] The research aimed to investigate the influence of polyvinyl alcohol and sodium alginate on the physical stability of microcapsule suspension and the corresponding rheological changes. [Method] The Lambda-cyhalothrin microcapsule suspension was prepared by the interfacial polymerization method. The physical stability of the sample was analyzed by Turbiscan LAB multiple light scattering stability analyzer. The rheology of the sample was determined by Discovery HR-2 rheometer. [Result] Under the same system, the higher the apparent viscosity and viscoelasticity, the more stable the sample. The stability kinetics index of 2.5% polyvinyl alcohol and 0.3% sodium alginate samples after 6 h dropped from 15.75 to 4.00 and 3.08, respectively , And tends to be stable. At low shear rate, apparent viscosity of 2.5% PVAc increased from 8.55 × 10 ~ (-3) Pa · s to 71.89 Pa · s, and the apparent viscosity of 0.3% sodium alginate increased To 28.19 Pa · s; At low scan frequency, the elastic modulus of 2.5% mass fraction polyvinyl alcohol sample increased from 0.03 Pa to 12.75 Pa, and the 0.3% mass fraction of sodium alginate increased to 3.96 Pa. [Conclusion] Appropriate addition of macromolecule polymer can change the spatial effect of sample, which can change the rheological behavior and improve the physical stability.