物理化学学报 >> 1998, Vol. 14 >> Issue (02): 109-114.doi: 10.3866/PKU.WHXB19980203

研究论文 上一篇    下一篇

由硅溶胶生长单分散颗粒的研究

董鹏   

  1. 石油大学重质油加工国家重点实验室,北京昌平 102200
  • 收稿日期:1997-04-10 修回日期:1997-06-23 发布日期:1998-02-15
  • 通讯作者: 董鹏

Preparation of Monodisperse Silica Spheres by Growth of Silica Sol Particles

Dong Peng   

  1. National Heavy Oil Research Laboratory,University of Petroleum,Beijing 102200
  • Received:1997-04-10 Revised:1997-06-23 Published:1998-02-15
  • Contact: Dong Peng

摘要:

针对现行单分散二氧化硅颗粒制备方法的粒径预见性差、步骤繁琐、收率低等问题,研究了一种用硅溶胶作为种子,在氨、水和乙醇的混合溶液中通过水解正硅酸乙酯(TEOS)生长出单分散颗粒的简便方法.该方法仅在初始的悬浮液中滴加TEOS即可使种子正常生长,无须补充氨水以修正体系浓度的变化.最终的分散相浓度可达10%(质量分数).可选择生长的粒径范围在1微米以内并可精确控制.所得颗粒粒径分布偏差优于Stober方法.讨论了种子数密度、生长环境和TEOS滴加速度对生长最终颗粒粒径分布偏差的影响.

关键词: 硅溶胶, 二氧化硅, 单分散体系, 播种生长

Abstract:

A new process for preparing monodisperse silica spheres was developed to improve the accuracy of predictable diameter of particle and simplify the experimental procedure. It involves growth of commercial silica sol particle in an original mixture solution of ammonia, water and ethanol with continuous introduction of tetraethoxysilane and without compensation for the decrement of water and ammonia concentrations during the formation of monodisperse spheres. The final concentration of silica can reach about 10% by weight in the reaction mixture. The desired diameter of the particles up to 1μm at choice can be controlled accurately. The deviation of particle size distribution was less than that of the Stober spheres. The influence of the number density of reactants, temperature and the flow rate of tetraethoexy silane on the deviation of the size distribution of final particles was investigated.

Key words: Silica sol, Monodisperse system, Uniform particle, Seeded growth