固-液反应包膜尿素膜的微结构与红外光谱特征及氮素释放特性研究  

Study on Membrane Microstructures and Characteristics of Infrared Spectra and Nitrogen Release of Solid-Liquid Reaction Coated Urea

作　　者：毛小云[1] 冯新[1] 王德汉[1] 孙克君[1] 廖宗文[1] 

机构地区：[1]华南农业大学资源环境学院,广州510642

出　　处：《中国农业科学》2004年第5期704-710,共7页Scientia Agricultura Sinica

基　　金：国家863计划环境友好型肥料研制与产业化资助项目(2001AA246023);广东省百项工程控释专用肥资助项目(2KB05601N);广州市重点科技攻关控释肥的技术研究与开发资助项目(2001Z02402)

摘　　要：应用扫描电镜和红外光谱仪对2种固-液反应型包膜尿素的膜结构及成膜机理进行分析,并结合水中氮素溶出特性探讨了膜的结构特征与控释性能的关系。结果表明,固-液反应型包膜尿素膜由固体颗粒间的紧密排列并通过液体胶联的多层叠加构成,叠加层间和单层固体颗粒间排列的紧密程度决定膜的孔隙度和孔径大小,且与包膜材料特性有关。对膜谱学特征研究表明,固、液2种包膜材料在复合成膜过程中固体粉末表面的O-H与液体包膜材料的双键位置有键合作用,这种键合作用是膜形成和保证膜强度的基础。2种包膜尿素氮素释放速度有较大差别,且与膜结构密切相关,膜的孔隙度和孔径大小是决定氮素溶出速率的关键因素。The membrane microstructures and their forming mechanism of two coated ureas formed through solid-liquid reaction were observed by scanning electron microscope and infrared spectra, the relation of the structuralcharacteristics and the nitrogen release feature were also discussed combining with nitrogen dissolution in water.Theresults showed that the membranes were made of solid particles, tightly connected each other and were piled up layer bylayer through liquid glue. Porosity and aperture of membrane were determined by compactness of pilled layers and theparticles in a single layer and also related to the characteristics of coating materials. Research of the infrared spectra ofmembrane, made of a solid powder and a liquid glue, has proved that O-H on the solid surface was bonded with the doublebond of the liquid glue, thus forming membrane and keeping it stable. It is found that the two coated ureas showed obviousdifference in nitrogen release due to their membrane structures, the porosity and aperture of membrane were critical factorsfor nitrogen release.

关 键 词：固-液反应包膜尿素膜 微结构 红外光谱特征 氮素释放特性 成膜机理 扫描电镜 包膜控释肥 

分 类 号：S145.2[农业科学—肥料学]