表面疏水型海藻酸钠微球保水剂缓释性能调控机制  

Regulating mechanism of slow-release performance of surface hydrophobic sodium alginate microspheres

作　　者：柳佳利 白波[1,2] 孙钰琨 LIU Jiali;BAI Bo;SUN Yukun(School of Water and Environment,Chang′an University,Xi′an 710054,Shaanxi Province,China;Key Laboratory of Subsurface Hydrology and Ecological Effects in Arid Region,Xi′an 710054,Shaanxi Province,China)

机构地区：[1]长安大学水利与环境学院,陕西西安710054 [2]旱区地下水文与生态效应教育部重点实验室,陕西西安710054

出　　处：《化学工程》2023年第10期30-35,共6页Chemical Engineering(China)

基　　金：中国博士后科学基金面上资助项目(2022M710481);中央高校基本科研业务费专项资金(300102291102)。

摘　　要：释水速度快与机械性能差极大地限制了海藻酸钠凝胶微球在保水方面的应用,表面疏水改性是改善上述问题的有效方法。以SA(海藻酸钠)和PVA(聚乙烯醇)组成的载水微球为基质,通过BW(蜂蜡)表面修饰,制备具有疏水缓释性能的环境友好型BW@SA/PVA复合微球。研究复合微球的微观结构、机械性能、溶胀性能和土壤保水性能,探讨BW@SA/PVA复合微球的保水调节机制。结果表明:复合微球表面的BW修饰层可有效地降低海藻酸钠凝胶微球孔隙度并提高微球的机械强度,从而使海藻酸钠凝胶微球内外水分的传质阻力得到显著增强。其中SA与BW质量比为1∶1的BW@SA/PVA复合微球具有最好的形貌结构和保水性能,相比于SA/PVA复合微球,BW@SA/PVA复合微球(1∶1)的机械性能提高了13.18%,土壤保水性能提高了26.11%,且在水中的溶胀过程遵循准二级动力学方程。Fast water release speed and poor mechanical properties limite the applications of sodium alginate gel microspheres in water retention.Surface hydrophobic modification is an effective strategy to solve these problems.The environmentally friendly BW@SA/PVA composite microspheres with hydrophobic and slow-release properties were prepared by surface modification of the microspheres composed of SA(sodium alginate)and PVA(polyvinyl alcohol)with BW(beeswax).The microstructure,mechanical properties,swelling properties and soil water retention properties of the BW@SA/PVA microspheres were investigated and the water retention regulation mechanism was also discussed.The results show that the BW hydrophobic layer can reduce the porosity of SA/PVA microspheres and increase the mechanical strength,so that the internal and external water mass transfer resistance were enhanced.The BW@SA/PVA microspheres with a mass ratio of SA to BW of 1∶1 have the best morphology,structure and water retention performance.Compared with SA/PVA microspheres,the mechanical properties and the soil water retention performance of BW@SA/PVA microspheres(1∶1)are increased by 13.18%and 26.11%,respectively,and their swelling process in water follows the quasi-second-order kinetic equation.

关 键 词：海藻酸钠凝胶微球 蜂蜡 表面疏水 保水剂 传质阻力 

分 类 号：S152.7[农业科学—土壤学] TB332[农业科学—农业基础科学]