乙草胺碳酸钙微球的制备方法及其缓释性能研究

为增加乙草胺的持效性,将乙草胺与氯化钙-十二烷基硫酸钠溶液混合后与碳酸钠反应制得乙草胺碳酸钙微球。通过扫描电镜、粒径分布仪及高效液相色谱等对该微球进行了表征,并对制备工艺、载药率及缓释性能等进行了探讨。结果表明:碳酸钙载体晶型主要为方解石结构;常温条件下,当n(CaCl2):n (Na2CO3):n(SDS)=1:2:2、搅拌速率为500 r/min、搅拌时间为10 min时,损耗率为0.2%,载药率接近20%;所得碳酸钙微球呈球形,粒径分布窄,且呈正态分布;微球中乙草胺的释放速率随温度和pH值的升高而增加。该微球制备工艺的优化及缓释性能研究结果可为田间定时、定量的释药研究及应用提供参考。

Study on preparation of acetochlor calcium carbonate microsphere formulation and its controlled release performance

After acetochlor was mixed with calcium chloride and sodium dodecyl sulfate (SDS) solution,acetochlor calcium carbonate microsphere formulation was prepared by making sodium carbonate react upon the mixture.The microsphere formulation was then characterized by SEM,particle size distribution and HPLC,and its preparation process,loading efficiency and release properties were studied.The results showed that the crystal structure of calcium carbonate carriers belonged to calcite structure;with n (CaCl₂):n(Na₂CO₃):n(SDS) as 1:2:2,and stirring speed of 500 r/min,stirring time of 10 min,the loading rate was nearly 20% and loss rate was 0.2% in room temperature.Simultaneously,the surface was spherical with narrow size distribution,which was normal distribution;the release rate of acetochlor from the microsphere formulation increased as the temperature and pH value increased.The results of present study would provide useful information for further investigation and application of timing and quantitative field release of pesticide in the future.