Latex-Bridged Inverse\nPickering Emulsion for Durable\nSuperhydrophobic Coatings with Dual Antibacterial Activity

There is agreement that every colloidal structure produces\nits\nown set of unique characteristics, properties, and applications. A\ncolloidal phenomenon of latex-bridged water in a dimethyl carbonate\n(DMC) Pickering emulsion stabilized by R202 hydrophobic silica was\ninvestigated for its ability to act as a superhydrophobic coating\n(SHC) for cellulose substrates. First, various emulsion compositions\nwere screened for their stability and droplet size. The final composition\nwas then cross-examined by cryogenic scanning electron microscopy\nand optical and fluorescent microscopy to verify the colloidal structure.\nThe drying pattern of the coating was investigated by using labeled\nsamples under a fluorescent microscope and by scanning electron microscopy\non a paper substrate. After the final ∼3 μm of dry coating\nwas applied, it exhibited superhydrophobicity (advancing contact angle\n= 155°) and full functionality after 5 min at room temperature\n(RT). Coated samples maintained superhydrophobicity after 20 abrasion\ncycles and mechanical integrity after 50 s of water immersion. The\nSHC-coated paper demonstrated compatibility with a standard laser\nprinter, and the coated paper demonstrated superhydrophobicity after\nprinting. Finally, a propolis/DMC extract was produced and then analyzed\nby gas chromatography–mass spectroscopy (GC-MS) and infused\ninto the SHC (PSHC). The newly formed PSHC demonstrated its ability\nto act effectively against E. coli biofilm\nand S. aureus planktonic cells and\nreduce their viability by over 90% and 99.99%, respectively.