Formation of Hierarchical Porous Structure via Breath Figure Method

Yongjian Zhang,Zhiguang Li

doi:10.1155/2018/1265479

Yongjian Zhang, Zhiguang Li

Open Access

https://doi.org/10.1155/2018/1265479

Copy DOI

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.

Highlights

Breath figure (BF) has attracted great attention to prepare patterned ordered porous polymer films because of its facile, economical, time saving, and convenient implementation [1,2,3]
The porous films of PS and silica nanoparticles of different -OH are prepared through breath figure method
The patterns of the film become more disordered with the enhancing concentration of nanoparticles, and the pore size is increased

Summary

Introduction

Breath figure (BF) has attracted great attention to prepare patterned ordered porous polymer films because of its facile, economical, time saving, and convenient implementation [1,2,3]. The BF method is an easy process to fabricate honeycomb patterned porous films because the water droplets are applied as templates and easy removed by simple evaporation. In this process, polymers dissolved in a volatile and water-immiscible solvent are cast under high humidity. After complete evaporation of the solvent and water droplets, hexagon-arranged honeycomb pores templating from water droplets are left on the polymer film surface. Ke et al [26] prepared positively charged honeycomb films from PS-based block copolymer and silica particles by the breath figure method. The porous structure films of the PS and silica nanoparticles of different surface hydrophobicity are fabricated from breath figure method. The influences of important experimental factors, such as humidity and particle hydrophobicity, on the final morphology are discussed

Experimental

Results and Discussion

Conclusions