Formation of Hierarchical Porous Structure via Breath Figure Method

Abstract

The porous structure films of PS containing silica nanoparticles of different hydrophobicity were obtained from breath figure method. For the porous films, the pores at the peripheral region and the center region were compared. It was found that the pores at the peripheral region appeared more uniform in size and showed higher degree of ordering. In addition, the patterns of the porous film became more disordered with the enhancing concentration of nanoparticles, and the pore size of the pore was increased. With the increase of the content of SiOH, that is, decrease in particle hydrophobicity, the Si elements were aggregated at the surface of the film and the interior of the pores. A hierarchical porous structure had been obtained at appropriate humidity and particle concentration. Finally, a possible mechanism of the hierarchical structure was proposed.