含多种天然组分保水剂的制备及其对KH2PO4的缓释效果研究

以天然产物腐植酸(HA)、羧甲基纤维素钠(CMC)、蒙脱土(MMT)为复合组分,丙烯酸为聚合单体,使用水溶液聚合法制备了一种含有多种天然组分的环境友好型保水剂,用红外光谱、扫描电镜和热重/差示扫描量热分析对保水剂的结构和热性能进行了表征。分析了聚合工艺条件如HA、MMT、CMC和交联剂用量对保水剂吸水倍数的影响规律。保水剂在蒸馏水和0.9%NaCl溶液中的吸水倍数分别为801倍和87倍。探索了保水剂对磷酸二氢钾(KH2PO4)的负载和缓释性能,结果表明,MMT的加入以及适度的交联可显著提高保水剂对KH2PO4的负载率,并有效减慢其对KH2PO4的释放率,HA可明显提高保水剂的吸水性能,但对KH2PO4的负载和释放影响不大。

Superabsorbents containing a variety of natural components:Preparation and slow release characteristics of monopotassium phosphate

Superabsorbents were synthesized by solution polymerization using acrylic acid (AA)as monomer,natural products such as montmorillonite(MMT),potassium humate(HA),carboxymethyl cellulose(CMC)as the additives.They were characterized by fourier transform infrared spectroscopy,scanning electron microscopy and thermogravimetry/differential scanning calorimetry.The effects of polymeric parameters such as MMT,HA,CMC and crosslinker content on the water absorbency were investigated.The maximum absorption ratio of the resulting composites in distilled water and 0.9% NaCl solution was up to 801 and 87 times,respectively.The composites were loaded with KH2PO4 and their potential for controlled release of this salt was investigated,the results showed that MMT and moderate crosslinking could improve their loading percent for KH2PO4 and reduce the release rate of KH2PO4 effectively,HA could improve the water absorbency of the superabsorbents,but it had little effect on the load and slow release of KH2PO4.