THE EFFECT OF MICROENCAPSULATION OF UREA USING POLYSTYRENE-POLYCAPROLACTONE BIOBLEND POLYMER ON ITS IN-VITRO RELEASE EFFICIENCY

Urea,a nitrogen fertilizer,is needed by plants, but its absorption is still in-optimal caused by very fast dissolved. It can cause also negative effects on the environment. This study aimed was to examine the effect of several ratios of polystyrene (PS)-polycaprolactone (PCL) bioblend polymers coating urea on the release efficiency of urea microcapsules. The microcapsules were produced in 3 formulas by varying the amount of PS:PCL in Formula F1, F2, and F3 at the ratio of 85:15, 90:10, and 95:5%, respectively. Urea particle size used was at a range of 1-10μm. Coating ordinary urea by microencapsulation technique using PS-PCL bioblend can produce the slower release of urea compared to ordinary urea but only lasts up to 45 minutes due to initial burst effect or fast release at the beginning of dissolution. The highest release efficiency of urea from coated urea was from Formula F2 (68.47%)and the lowest one was from Formula F3 (61.83%).