保水包膜尿素肥料理化特征

保水肥料是缓/控释肥料剂一个新的发展方向。本文中作者对研发的一种保水缓释包膜尿素肥料的包膜物理化学特征,养分缓释机制进行了研究。电镜观察显示,保水材料包膜上存在网状孔隙,膜厚度0.12mm~0.30mm,是水分贮存的物理空间。红外光谱分析表明,保水材料与尿素表面存在着氢键作用,这种氢键作用使保水包膜材料对尿素有一定吸附作用,这是保水包膜尿素具有养分缓释的一种机制。吸水倍率测定表明,保水包膜材料吸水倍率在70倍以上,吸水达饱和的时间为1.4小时,在盐水中还有一定的吸水倍率,pH为6.87。因此,保水包膜尿素肥料是水肥复合一体化的缓释肥料。

Physical and Chemical Characteristics of Water-Absorbent Coated Urea

Water-absorbent fertilizer is a new kind of slow/controlled release fertilizers(SRFs/CRFs).A study was conducted on the physical and chemical characteristics of coatings and mechanism of nutrient slow release of water-absorbent coated urea(WACU).The result of Scanning Electronic Microscopy(SEM) indicates that there is much network-like porosity in coatings on the fertilizer which should be physical space where can store water.The coatings of water-absorbent material is 0.12mm～0.30 mm in thickness.The result of IR spectrum shows that water-absorbent materials are associated with surface of urea granular by hydrogen bond,and the water-absorbent materials could adsorb or combine certain amount of urea,which is one of mechanisms to the slow release of WACU.The test results of water absorbency shows that the coatings of water-absorbent materials have 70g g-1 in water absorbency,the time of water-absorbing saturation is about 1.4 hours,and pH value is 6.87.Thus,water-absorbent coated urea is a new slow release fertilizer incorporating fertilizer and water-absorbent polymer all in one.