Abstract:
a novel slow-release nitrogen fertilizer poly(carbonyl urea)oligomer (PCUO) was prepared by the condensation polymerization of urea and dipropyl carbonate (DPrC) at normal pressure, in which anhydrous potassium carbonate was as a catalyst. The oligomer was characterized by FT-IR, ¹H-NMR, and ¹³C-NMR spectroscopy, which showed that the average degree of PCUO was 1 to 5. The effects of the molar ratio of urea to DPrC, reaction time as well as the temperature on the yields were investigated and optimized. In addition, the slow-release behaviour of PCUO was evaluated in distilled water, which revealed that the product had good slow-release property.