摘要
用正交试验,采用L9 (33)正交表,在醇水体系中采用氨作催化剂,正硅酸乙酯为硅源,研究了各原料浓度对单分散球形SiO2 粒度的影响。研究表明在其它条件不变的情况下,二氧化硅的粒度随着氨和水浓度的增加而明显增大,随TEOS 浓度的增加,二氧化硅的粒度也略有增大,但幅度较小。本文还详细研究了二氧化硅颗粒的形成机理。
The mono-disperse spherical silica was synthesized in EtOH-H2O-NH3 system. With orthogonal design, the influence of raw material concentration on the size of silica was discussed. The results indicate that the size of silica enhances greatly with the concentration of ammonia, which provides a stronger nucleophilic reagent and promotes the hydrolysis of TEOS obviously. The size of silica also increases with the concentration of TEOS, but with a much less extent. When the percentage of water increases, that of ethanol decreases at the same time, both lead to the growing up of silica particles. The formation mechanism of silica was also discussed in detail. The process of formation of mono-disperse spherical silica can be divided into two parts: hydrolysis and condensation. The former was the key step and the factors which affect the speed and the extent of hydrolysis also influence the size of silica particles greatly.
出处
《功能材料》
EI
CAS
CSCD
北大核心
2005年第4期577-579,共3页
Journal of Functional Materials
基金
国家自然科学基金资助项目(59876045)
