利用农作物秸秆合成树脂包膜材料来替代资源不可再生的石化产品类包膜材料是研发高效、低成本、环保型控释肥料的发展方向。本申请在前期研究中明确了利用有机硅化合物改性秸秆合成树脂包膜的超大颗粒控释肥具备优良养分控释性能和节省膜材的特点，但是该有机硅改性秸秆合成树脂包膜超大颗粒控释肥养分控制释放的机理还不清楚。本项目拟通过研究疏水性有机硅化合物在秸秆合成树脂膜壳表面、膜材内以及微孔通道中的分布及存在状态，探讨其对水分进入膜内与养分溶出膜外的作用机制，并研究有机硅改性秸秆合成树脂膜和超大肥料颗粒共同对养分控释性能影响的叠加效应及其调控机制，揭示有机硅改性秸秆合成树脂包膜超大颗粒控释肥养分释放的控释机理，为完善利用农作物秸秆类物质合成树脂膜材，研发高效、低成本、环保型包膜控释肥提供理论与技术指导。

Using straw synthetic resin as a substitute for non-renewable petroleum products as coating materials for controlled-release fertilizers provides great option for the development of high-efficiency, low-cost, and environmental-friendly fertilizers. Our preliminary research indicates that extra large fertilizer tablets coated with organic silicon modified straw synthetic resin possess characteristics of excellent controls on nutrient releases and low usage of coating materials. However, the mechanisms of controlling nutrient releases from extra large fertilizer tablets which were coated with organic silicon modified straw synthetic resin are not well understood. The proposal of this application is to (1) characterize the influx of water and the outflux of nutrients through the membrane of the modified straw resin by determining the distribution and state of the hydrophobic organic silicon compound on the membrane surface, within the membrane, and in the micro-pore channels; (2) understand the synergic effects of organic silicon modified straw synthetic resin membrane and extra large fertilizer tablets on the nature and behavior of controlling nutrient releases; and (3) reveal the mechanisms of controlling nutrient releases of extra large fertilizer tablets coated with organic silicon modified straw synthetic resin. The proposed research will ultimately provide both fundamental information and practical technology for the development and optimization of high-efficiency, low-cost, and environmental-friendly controlled-release fertilizers using straw synthetic resin.