生分解性高分子による遅効性肥料の調製

Many fertilizers are soluble in water, therefore their effect does not last for long time after fertilizing in soils. The nitrogenous fertilizers such as urea transported to groundwater cause serious agricultural contamination and health problems. To solve these problems, sustained release of fertilizer has attracted much attention. In this study, we attempted to prepare polylactide microcapsules with fertilizer by phase separation technique, which was a method of microencapsulation. Polylactide (PLA) was used as a biodegradable polymer bacause the biodegradable polymer has no influence on the soil and the ecosystem. The effect of preparation conditions such as stirring time and fertilizer concentration on morphology of microcapsule and on cumulative percentage released of enclosed urea was also investigated.