微乳液法制备条件对纳米SiO_2粒子形貌和粒径分布的影响

研究TritonX - 10 0 /正辛醇 /环己烷 /水 (或氨水 )微乳液稳定相行为与制备条件的关系 ,发现K〔m(TritonX - 10 0 )∶m(正辛醇 )〕 =1 5 ,而水相是氨水时微乳液系统有较宽单相W/O型微乳区 ,是正硅酸乙酯 (TEOS)水解制备纳米SiO2 粒子的适宜介质系统。在h〔n(H2 O)∶n(TEOS)〕 =4 ,R〔n(H2 O)∶n(TritonX - 10 0 )〕 =6 5和K =1 5的条件下 ,TEOS受控水解制得疏松球形无定形晶态SiO2 粒子 ,粒度分析表明 99 7%粒径为 4 0～ 5 0nm

Dependence of Particle Morphology and Size Distribution of Nanosize Silica Synthesized in W/O Microemulsion on Preparation Conditions

The relationship between the phase behaviors of the microemulsions,consisting of water,Triton X-100,octanol and cyclohexane,and the preparation conditions was examined.It was found that in the triangle phase diagram there exists a larger region relating to single phase microemulsion of W/O type,which might be a proper medium system for synthesizing nanosize SiO 2 particles by hydrolysis of tetraethylorthosilicate(TEOS).Under the favorable conditions,i.e. R 〔 n (H 2O)∶ n (Triton X-100)〕=6 5, h 〔 n (H 2O)∶ n (TEOS)〕=4 and K 〔 m (Triton X-100)∶ m (octanol)〕=1 5,nanosize porous crystal SiO 2 particles were obtained, with a diameter range of 40-50 nm for about 99 7% percents of the particles.