2018 Xiang Granular, Slow-Release Fertilizer from Urea-formaldehyde, Ammonium Polyphosphate, and Amorphous Silica Gel- A New Strategy Using Cold Extrusion
A new granular, slow-release fertilizer prepared by a cold-extrusion strategy (GSRFEx) based on ureaformaldehyde (UF), ammonium polyphosphate (APP), and amorphous silica gel (ASG) was presented. Characterizations showed that there were strong hydrogen-bond interactions and good compatibility among UF, APP, and ASG in GSRFEx. The mechanical properties as well as the slow-release properties of GSRFEx were greatly enhanced after the addition of APP and ASG to UF. Rape pot experiments indicated that GSRFEx could improve N-use effi ciency dramatically and thereby facilitate the growth of rape. Importantly, as an economical, eff ective, and environment-friendly technology, cold extrusion has great potential to be applied in horticulture and agriculture. We hope that our work can off er an alternative method for the design of slowrelease fertilizers with desirable properties.