Fabrication of polymeric and silica ceramic porous microstructures by perfluoropolyether based soft lithography

Various porous micropatterns were successfully fabricated by closely packing polystyrene (PS) spheres and silica beads in the grooves on the surface of a PDMS mold, which were obtained by a direct evaporation-induced self-assembly method. Subsequently, UV-cured acrylated perfluoropolyether with low surface energy easily enabled the transfer of the perfluoropolyether-filled composite patterns in PDMS mold onto a substrate. Three-dimensional (3D) ordered perfluoropolyether or silica ceramic porous microstructures were prepared by removal of PS spheres or perfluoropolyether binder as the sacrificial materials, respectively. Moreover, line, grid and circle shapes of porous micropatterns in a single layer or double layers were also fabricated with the aid of different shaped PDMS molds.