摘要：通过正交试验设计,用L₉(⁴₃)正交表安排实验,在醇氨反应体系中采用溶胶-凝胶(sol-gel)法制备单分散球形SiO₂,运用直观图和极差分析确定各主要原料对制备不同粒径SiO₂的影响,优化配比。研究表明:对单分散球形SiO₂的平均粒径的影响次序为:用水量、醇用量、氨水和正硅酸乙酯(TEOS)用量。通过控制反应条件,可实现在一定范围内获得尺寸均一、不同粒径、分散性好的球形SiO₂。制备出的单分散球形SiO₂颗粒形态完整,粒径140～500nm,分布窄、单分散性好。

关键词： 正交试验;球形SiO₂;单分散性;溶胶-凝胶(sol-gel)法;正硅酸乙酯

Abstract：T he mono-dispersed spherical silica is synthesized in the ethanol－ammonia reaction system through sol－gel process with orthogonal design．Based on the analysis of the frank plot and the difference，the influence of synthesis varied spherical silica in different diameter，employed the main raw materials，are ascertained．T he studies indicate that the order of the grade influencing the average diameter is the water content is in the first place，ethanol the second，ammonia the third，and tetraethylorthosilicate the last．By means of controlling reaction system， the mono-dispersed spherical silica can be obtained in a special scope，and the particles is uniformed，and in different diameter and mono-dispersed．T he mono-dispersed spherical silica is in a full morphology，and in 140～500 nm diameter．T he particles are dispersed in a narrow scope and have mono-dispersed state． It is found that the formation of mono-dispersed spherical silica experienced three stages：the micro-nuclei formation stage，nuclei growth stage，and when particles reached their full size，and turned more stable and dense．It is also fouund that the key of producing uniform particles is fast nuclei formation speed and the separation of nuclei formation and growth processes． 

Keywords：orthogonal design；spherical silica；mono-dispersed； sol－gel process；tetraethylorthosilicate