Fluorinated Raspberry-like Polymer Particles for Superamphiphobic Coatings

Raspberry-like (RB) polymer particles were prepared, fluorinated, and cast onto glass plates to yield highly water- and oil-repellant superamphiphobic particulate coatings. To procure the RB particles, glycidyl-bearing 212 and 332 nm particles (abbreviated as s-GMA and l-GMA, respectively) were first prepared via surfactant-free free radical emulsion polymerization. Reacting the glycidyl groups of the l-GMA particles with 2,2'-(ethylenedioxy)bis-(ethylamine) (EDEA) produced large amine-functionalized particles (l-NH2). The l-NH2 particles were then reacted with an excess of the s-GMA particles to create RB particles. For surface fluorination, the residual glycidyl groups of the smaller s-GMA particles surrounding the central 1-NH2 core of the RB particles were first converted to amino groups by reaction with EDEA. The purified amino-bearing particles were subsequently reacted with an excess of a statistical copolymer poly(2-(perfluorooctyl)ethyl methacrylate-co-glycidyl methacrylate), P(FOEMA-co-GMA). Casting these particles onto glass plates yielded particulate films that exhibited static contact angles of 165 +/- 2 degrees, 155 +/- 30 degrees, 152 +/- 4 degrees, and 143 +/- 1 degrees and droplet rolling angles of <1 degrees, <1 degrees, 7 +/- 2 degrees, and 13 +/- 2 degrees for water, diiodomethane, corn-based cooking oil, and hexadecane droplets, respectively. These results demonstrated that this practical bottom-up approach could be used to produce superamphiphobic coatings.