Research on Preparation and Properties of Urea-formaldehyde Fertilizer Modified byMontmorillonite

Objective The slow and controlled release fertilizers with excellent nitrogen slow-release performance and simple preparation process were developed.

Method A new kind of biodegradable polymer with interlayer structure was prepared by solution polymerization, where montmorillonite(MMT)with nanometer layer structure was interspersed with urea-formaldehyde(UF), a slow-release polymer fertilizer containing nutrients. The structure of the prepared fertilizer was characterized by FTIR and XRD. The surface morphology of the fertilizer was observed by SEM. The influence of the ratio of raw materials on molding performance of the fertilizer was studied, and the release characteristics of the fertilizer in still water was determined.

Result The dynamic rheological properties of the prepared slow-release fertilizer can be greatly improved with the addition of MMT. In addition, it has an excellent sustained release effect on nitrogen, and the maximum cumulative release rate of nitrogen is 38.79% when cultured in still water for 70 days, indicating that the slow-release properties of crystalline polymers can be improved by destroying the original crystal structure.

Conclusion The results have reference significance for solving the problem of low sustained release performance caused by high crystallinity of slow-release chemical synthetic fertilizer urea-formaldehyde, the most commonly used chemical synthetic fertilizer at present.