(417h) Selective Deposition of Fluoropolymers Using Surface Energy Contrast

We introduce a simple method for the selective deposition of fluoropolymers and fabrication of free-standing porous membranes using initiated chemical vapor deposition (iCVD). Here, the iCVD processing condition was chosen in order that the super-saturation condition for the monomer allows for selective wetting of the surface. We used surface energy contrast, artificially created on the substrate, to selectively deposit thin films of hydrophobic materials on the substrate. We measured the heat of adsorption of the monomer on different substrates to understand the effect of surface energy on the monomer adsorption on a variety of substrates. While the monomer saturation parameter (p/p_sat) was kept in the range of 5 to 10, the monomer condensed on the high surface energy area due to a favored wetting condition. Additionally, we placed a piezoelectric resonant system under the cooling stage to further assist nascent liquid droplets migrating towards the high surface energy regions. As a result, we can demonstrate spatial selectively in the polymerization of 1H,1H,2H,2H-perfluorodecyl acrylate (PFDA) on the high surface energy area of the template using Perfluoro-1-buranesulfonyl fluoride as an initiator. The polymer stoichiometry, coatings and coverage, and the surface topography were confirmed by x-ray photoelectron spectroscopy, scanning electron microscopy, and atomic force microscopy, respectively.