Abstract A novel hydrogel slow-release nitrogen fertilizer based on sawdust with water absorbency was prepared using grafting copolymerization. Urea was incorporated as nitrogen source in a hydrogel fertilizer. Potassium persulfate (KPS) and N,N᾽-methylenebis acrylamide (MBA) were used as the initiator and cross-linker, respectively. The structure and properties of the samples were characterized by XPS, EDS, SEM, XRD and FTIR. The effects of various salt solutions, ionic strength and pH on swelling behavior were discussed. The results showed that the largest water absorbency of the sample reached 210 g/g in distilled water. In addition, the sample had the good nitrogen release property. Thus, the novel environmentally friendly hydrogel fertilizer may be widely applied to agricultural and horticultural fields.

中文翻译：

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用于环保缓释肥料的木屑纤维素水凝胶的制备及性能

摘要 采用接枝共聚方法制备了一种新型水凝胶缓释氮肥，以具有吸水性的木屑为原料。尿素作为氮源掺入水凝胶肥料中。过硫酸钾 (KPS) 和 N,N᾽-亚甲基双丙烯酰胺 (MBA) 分别用作引发剂和交联剂。通过XPS、EDS、SEM、XRD和FTIR对样品的结构和性能进行了表征。讨论了各种盐溶液、离子强度和 pH 值对溶胀行为的影响。结果表明，样品在蒸馏水中的最大吸水率达到210 g/g。此外，该样品具有良好的脱氮性能。因此，该新型环保水凝胶肥料可广泛应用于农业和园艺领域。