Controlled-release fertilizer based on poly(butylene succinate)/urea/clay and its effect on lettuce growth

Controlled-release fertilizer is one of the most critical tools in agribusiness for decreasing environmental impacts. Thus, the development of bio-based systems able to induce the slow release of fertilizers has become the focus of numerous researchers. In this sense, this work presents a slow-release fertilizer prepared by melt mixing of poly(butylene succinate) filled with 30 wt % urea and 5 wt % montmorillonite clay. The obtained materials were characterized using FTIR, XRD, and SAXS. Also, the release of urea was investigated using gravimetric and spectrophotometric tests. Finally, a vegetable growth analysis was performed to evaluate the development of lettuce (Lactuca sativa L.). The best composite material can increase the diameter of the lettuce by 67%, whereas the conventional use of urea increased this diameter by 48%. Therefore, the presented materials are useful as fertilizer systems.