纳米氧化锌的合成及表面改性

以硫酸锌、尿素为原料,采用均相沉淀法合成了纳米氧化锌.研究了硬脂酸对所制的纳米氧化锌粉体表面改性的机理及其对粉体亲油性的影响.实验结果表明,硬脂酸中的羧基与纳米氧化锌粉体颗粒表面的羟基发生了酯化反应,并在表面形成单分子膜.经过表面改性的纳米氧化锌由亲水性转化为亲油性.同时,就纳米氧化锌粉体硬脂酸表面改性反应,探讨了反应摩尔分数、反应温度和反应时间对产物的影响,从而筛选出粉体亲油性最大的反应条件为:硬脂酸质量分数为7%;反应温度为50℃;反应时间为1h.

Synthesis and Surface Modification of Nanometer ZnO Powder

Using ZnSO_4.7H_20 and urea as raw materials, nanometer ZnO was prepared by homogeneous precipitation method. Nanometer ZnO was characterized by XRD and TEM. The surface of nanometer ZnO powders was modified with stearic acid. A covalent bond was formed by chemical reaction between the surface hydroxylic groups that were present on the surface of nanometer ZnO powders and organic long-chain molecules such as stearic acid. The surface of ZnO powders was coated with a monomolecular layer of aliphatic chains. The polarity of nanometer ZnO powders was changed to non-polarity. The effects of concentration, reaction temperature and reaction time on the surface modified nanometer ZnO powders were discussed.