Abstract：
Chemical modification of sodium alginate (SA) polymer chains can increase its functional group species. Sodium periodate (SP) was usually used to oxidize the hydroxyl groups on the chain of SA to aldehyde groups, the preparation of oxidized sodium alginate (OSA) using SP is not only complicated, also limits the variety of functional groups on the chain of OSA. By contrast, we have developed an innovative strategy for OSA, in which ammonium persulfate (APS) was used to oxidize SA, providing a clear elucidation of the oxidizing process and mechanism. OSA/PAM hydrogels were synthesized using OSA, the hydrogels possess excellent adhesion properties to various non-metallic and metallic substrates. Tensile and compression tests show that the cross-linked OSA/PAM hydrogels have superior mechanical properties. We exploit OSA/PAM hydrogels as soil adhesive and water-retaining agents for wheat growth. OSA/PAM hydrogels significantly improve the survival time of wheat grown in brown loam soil under a water-shortage environment, and slow down the wilting of wheat in a water-shortage environment and prolong the survival time of wheat in sandy soils. Our trials should make hydrogels important for wheat cultivation in brown loam soils and the development of desert areas.
摘要：
海藻酸钠（SA）聚合物链的化学修饰可以增加其官能团种类。高碘酸钠（SP）通常用于将SA链上的羟基氧化为醛基，用SP制备氧化海藻酸钠(OSA)不仅复杂,也限制了OSA链上官能团的多样性。相比之下,我们为OSA制定了创新战略，其中过硫酸铵（APS）用于氧化SA，提供了一个清晰的说明氧化过程和机理。使用OSA合成OSA/PAM水凝胶，水凝胶对各种非金属和金属基材具有优异的粘附性能。拉伸和压缩测试表明，交联的OSA/PAM水凝胶具有优越的力学性能。我们利用OSA/PAM水凝胶作为小麦生长的土壤粘合剂和保水剂。OSA/PAM水凝胶显著提高了小麦在缺水环境下生长在棕壤土上的存活时间,减缓缺水环境下小麦的枯萎，延长小麦在沙质土壤中的存活时间。我们的试验应该使水凝胶对于棕色壤土中的小麦种植和沙漠地区的发展很重要。
