表面修饰二氧化硅微球的制备、表征及分散性能

采用一步法制备了亚微米纯二氧化硅微球及8种有机硅表面修饰的二氧化硅微球,用扫描电镜、氮吸附、零电荷点测定等方法对微球进行了表征,对比研究了微球在不同介质中的分散性能。所有微球都呈球形,形貌较好,依表面修饰基团的不同,粒子直径在0.42~0.54nm之间。所有微球均为实心,比表面积均小于21m2/g。微球的零电荷点在8.25~8.93之间变化。粒子经过表面修饰后,在不同介质中表现出了不同的分散行为,微球的分散行为可以由微球的亲水及疏水性,以及DLVO理论得到基本解释。

Preparation,Characterization and Dispersion Behavior of Surface Modified Submicrometer Silica Spheres

The pure submicrometer silica spheres and eight kinds of surface modified submicrometer silica spheres were prepared through a one-step process. Scanning electron microscopy(SEM), nitrogen sorption, and the determination of point of zero charge (PZC) were used to characterize the modified and pure silica particles. The dispersion behavior of the particles in different media was investigated. The SEM images of the particles demonstrated that all the particles were spherical particles with good shape. The diameter of the particles ranged from 0.42 to 0.54 nm depending on the surface modification groups. All the particles were nonporous particles with a surface area smaller than 21 m2/g, and a PZC between 8.25 and8.93. After modification, the particles presented different dispersion behavior, which were basically explained by considering the hydrophilicity and hydrophobicity of the particles and the DLVO theory.