明胶接枝丙烯酸/丙烯酰胺缓释肥新型包膜材料的制备与应用

以过硫酸钾为引发剂,N,N’-亚甲基双丙烯酰胺为交联剂,采用自由基聚合法使明胶与丙烯酸/丙烯酰胺进行接枝共聚,制备了一种明胶接枝丙烯酸/丙烯酰胺保水性缓释肥新型包膜材料,进行了吸水、保水、耐盐性检验并应用于包衣尿素的制备。结果表明:明胶用量为2.5%时,材料具有最大吸水率,在去离子水中达775 g/g,在自来水中为395 g/g。包衣尿素的氮素24 h和28 d释放率分别为12.11%、73.49%,缓释周期长达56 d,达到"缓释肥国家标准"。

Preparation of Coated Material for Slow Release Fertilizer by Grafting Gelatin with Acrylic Acid/Acrylamide and Its Application

A water retention coated material for slow release fertilizer were prepared by graft copolymerization of gelatin with acrylic acid/acrylamide,during which the potassium persulfate was used as the initiator and the N,N’-methylenebisacrylamide was used as the cross-linking agent.Then,the water absorption,the water retention and the salt tolerance of the coated material were verified in order to apply in coated urea.When gelatin amount was 2.5%,the coated material had the best water absorption that was 775 g/g in deionized water and 395 g/g in tap water.The results showed that release rate of nitrogen from coated urea at 24 h and 28 d was 12.11% and 73.49,and the releasing period of coated urea reached 56 d,which meet the requirments of National Standards for Slow Release Fertilizers.