Size-Controllable Synthesis of Worm-Like SiO2 Microspheres Using Dodecylamine as Direct Agent in Ethanol/Water Solvent System
Size-controllable synthesis of worm-like microporous monodispersed SiO2microspheres using dodecylamine (DDA) as direct agent in ethanol-water solvent system was firstly developed by varying the proportion of reactants. The products were characterized with scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), small angle X-ray diffraction (SAXRD) and nitrogen adsorption. The results showed that the SiO2microspheres with size of 50nm~1um could be prepared by varying the molar ratio of water/ethanol when the molar ratio of (DDA)/tetraethyl orthosilicate (TEOS) is 0.4 and the concentration of TEOS varied from 0.138 to 0.248mol/L. This method is simple and convenient, the prepared SiO2microspheres are monodispersed and uniform, the worm-like pore size is about 1.4nm. The size controllable silica microspheres could be used as an excellent additional medium to alter rheological behavior of fluid after surface modification..