Investigation of Degradation of Starch Complex for CRF Application

Controlled-release fertilizer (CRF) is applying a biodegradable material as a coating material to control release the nutrients from the urea. One of the cheap and easily available biodegradable materials is starch, and these properties enable it to be used as coating material for CRF application. However, starch itself has a few disadvantages and thus needed to be modified in order to overcome such drawbacks. Researches are yet to be done to determine a starch full potential as CRF. In this study, tapioca starch is chemically modified with urea in the presence of borate.
This study uses two important conditions for biodegradation to take place, which are moisture content and temperature as the study’s parameter for a period of 10 days. It is found that the soil’s different moisture content does not take any major part in the degradation of the starch complex as degradation takes place slowly and evenly throughout the experiment whereas a high temperature environment allows the starch complex to degrade faster. It then degrades steadily and slowly after Day 2.
However, an analysis shows that the nitrogen release by the starch complex film in semi-solid state under the two parameters is below 2%. The results might have been affected by the semi-solid samples, short time frame of sample’s collection and lack of microorganisms’ presence.