Al Rohily Khalid, El-Hamshary Hany, Ghoneim Adel, Modaihsh Abdullah
Department of Soil Science, College of Food and Agricultural Sciences, King Saud University, P.O. Box-2460, Riyadh 11451, Saudi Arabia.
Chemistry Department, College of Science, King Saud University, Riyadh 11451, Saudi Arabia.
ACS Omega. 2020 Dec 14;5(51):32919-32929. doi: 10.1021/acsomega.0c03740. eCollection 2020 Dec 29.
Two controlled-released fertilizers of phosphorylated alginate grafted with polyacrylamide (P-Alg--PAM) were synthesized. Monoammonium phosphate (MAP) and diammonium phosphate (DAP) were reacted with a matrix of sodium alginate (Alg) and poly(vinyl alcohol) (PVA). The phosphorylated matrix was then grafted with acrylamide. The obtained fertilizer materials showed excellent water absorbance. The controlled-release behavior of phosphorylated alginate grafted with polyacrylamide (P-Alg--PAM) was investigated at normal pH and 25 °C. The fertilizer materials exhibited release of phosphorus up to 77% for the MAP sample and up to 57% for the DAP sample till the forty fifth day of the application at pH 7 and 25 °C. More importantly, when the release experiments were conducted in calcium chloride medium, the fertilizers were able to release phosphorus efficiently with slight decrease until the forty fifth day of the application, suggesting that the presence of Alg in the fertilizer formulation may help in extending the duration for which phosphorus is available to the plant.
合成了两种接枝聚丙烯酰胺的磷酸化海藻酸盐控释肥料（P-Alg--PAM）。磷酸一铵（MAP）和磷酸二铵（DAP）与海藻酸钠（Alg）和聚乙烯醇（PVA）的基质反应。然后使磷酸化基质与丙烯酰胺接枝。所获得的肥料材料表现出优异的吸水性。在正常pH值和25℃下研究了接枝聚丙烯酰胺的磷酸化海藻酸盐（P-Alg--PAM）的控释行为。在pH值为7和25℃的条件下，直到施肥后的第四十五天，肥料材料中MAP样品的磷释放量高达77%，DAP样品的磷释放量高达57%。更重要的是，当在氯化钙介质中进行释放实验时，肥料能够有效释放磷，直到施肥后的第四十五天磷释放量略有下降，这表明肥料配方中Alg的存在可能有助于延长植物可利用磷的持续时间。
