摘要：采用酯化反应法,以水为溶剂,采用硬脂酸对纳米ZnO的表面进行改性,对改性效果进行测试表征。其最佳工艺条件为:硬脂酸质量分数为6%,反应温度为90℃,反应时间为90 min。结果表明,改性后的ZnO粒子呈纳米级的分散,亲油化度值达到72.31%,吸水率达到3.04%;经表面改性的纳米ZnO表现了很好的亲油疏水性;改性后的纳米ZnO表面引入了硬脂酸的官能团,使其表面羟基的数目明显减少,其改性机理为纳米ZnO表面羟基与硬脂酸分子中的羧基发生了类似醇和酸的酯化反应。

关键词：硬脂酸；表面改性；纳米粒子；酯化反应

Abstract：Using the distilled water as solvent,stearic acid was used to modify the surface of ZnO nano-particles by esterification method.The effect of modification was measured and characterized.The optimum conditions were that the mass fraction of stearic acid,reaction temperature and reaction time were 6%,90 ℃,90 min,respectively.The results show that the modified ZnO nano-particles are dispersed in nano-level and the lipophilic value and water absorption are 72.31% and 3.04% respectively.The modified ZnO nano-particles have well lipophilic.IR spectra shows that the functional groups of stearic acid are introduced to the surfaces of modified ZnO nano-particles,and the number of hydroxyl groups on the surfaces is significantly reduced.The modification mechanism is that the hydroxyl groups on the surfaces of ZnO nano-particles react with the carboxyl groups of stearic acid by esterification.

Keywords：stearic acid；surface modification；nano-particles；esterification