醇盐水解法制备单分散球形SiO2微粒

运用扫描电镜、透射电镜、激光粒度仪等测试手段，研究了以正硅酸乙酯为原料，用醇盐水解法制备ＳｉＯ＿２超微颗粒的微粒形成机理。通过控制催化剂浓度及反应温度等工艺条件，使硅酸单体浓度尽可能高而仅低于临界过饱和度，制得了单分散球形ＳｉＯ＿２超微颗粒，粒径为６０～５００ｎｍ。同时将加料速率、陈化时间等因素对微粒粒度及其分布的影响作了研究。

Synthesis of Monodispersed and Spherical SiO_2 Particles by the Controlled Hydrolysis of Metal Alkoxide

By means of SEM,TEM,laser scattered particle analyzer,etc,,the forma-tion mechanism of ultrafine SiO_2 particles behaved by the controlled hydrolysis of metalalkoxide was studied.By controlling concentration of reactants and catalyst,the concentra-tion of silicic acid monomer was set as high as possible,but just below the critical supersatu-ration.Under these conditions,monodispersed and spherical ultrafine SiO_2 powder could beprepared.The average particle size was from 60 to 500 nm. It was demonstrated that the re-action temperature,feeding speed,ageing time affected the particle size and distribution.