壳聚糖包膜缓释钾肥的初步研究

The preliminary study on the slow-release fertilizer of potassium coated by chitosan

以壳聚糖和KC l为主要原料制备壳聚糖包膜KC l的微球,测定了微球在25℃水中浸泡后K+的释放速率,并应用扫描电子显微镜对浸泡前后微球表面膜结构进行表征。结果表明:壳聚糖对K+的包埋率达到97.08%;K+释放量增量表现为,1-4 d快速上升,5-59 d稳定上升,60 d后开始减缓。扫描电镜观察结果表明:微球浸泡前表面膜结构密实;浸泡73 d后微球表面膜形成大量突起、均匀的小孔。24和28 d包膜微球在水中的释放量均符合缓释肥料标准。

The micro-ball of potassium coated by chitosan was prepared by using chitosan and potassium chloride as materials. The K ^＋ releasing rates of the micro-ball soaked in water （25 ℃）were detected and the apparent shapes of the micro-ball were examined by scanning electron microscope （SEM）. The results showed that, the enveloped rate of K^＋ in the micro-ball was 97.08% ; the K^＋ releasing curve was performed ascending sharply in 1 -4 days, then climbing stably in 5 -59 days and rising slowly after 60 days. The SEM results showed that the surface of micro-ball was compact and tight before soaked in water, but porous and expansile after soaked 73 days in water. The properties of micro-ball measure up to the criterion of slow-release fertilizers.