淀粉/聚乙烯醇包覆尿素膜的制备及其性能

Preparation and properties of starch/polyvinyl alcohol membrane coated urea

用可降解材料包覆的控释肥料可以减少肥料损失及对环境的污染。以玉米淀粉、土豆淀粉、聚乙烯醇(PVA)为原料,在交联剂甲醛和增塑剂甘油的作用下,通过溶解、糊化、再交联等工艺过程,制得肥料包膜料液,用此料液制备了包膜尿素。考察了玉米淀粉∶土豆淀粉(质量比)以及用碱改性玉米淀粉对包膜尿素缓释性能的影响。结果表明,玉米淀粉∶土豆淀粉(质量比)=8∶2,总淀粉∶PVA=10∶9时,制备的包膜尿素缓释性能最好,用碱改性的玉米淀粉并不能提高包膜尿素的缓释性能。将包膜尿素进行土壤降解实验,发现该膜在土壤中完全降解时间为45d左右。此包膜材料缓释性能良好,具有成本低、可生物降解、无环境污染等特点。

Using degradable material coated controlled release fertilizer, can reduce the fertilizer loss and pollution of the environment. Corn starch, potato starch, polyvinyl alcohol （ PVA ） as raw material, a cross linking agent in formaldehyde and plasticizer glycerin role, by dissolving, gelatinization, cross linking process, produce fertilizer coating liquid, the liquid preparation of the coated urea. Corn starch potato starch is investigated： （mass ratio）, alkali modified corn starch, the coated urea slow-release effect. The results showed that corn starch potato starch （mass ratio） = 8 ： 2, PVA=10 ： 9, total starch= preparation of coated urea slow release performance of the best, with alkali modification of corn starch can improve the coated urea slow release performance. The coated urea in soil degradation experiment, found the film of complete degradation in soil in time for 45 days. The film material delivery performance is good, has the advantages of low cost, biodegradable, no environment pollution etc.