Hierarchical, Plasma Nanotextured, Superamphiphobic Polymeric Surfaces

Abstract

A facile, mass production amenable, rapid method for making superamphiphobic / amphiphobic surfaces by random plasma nanotexturing of polymers in plasmas is presented. Plasma etched and simultaneously randomly roughened (nanotextured) polymethylmethacrylate (PMMA) Polyether-ether-ketone (PEEK), Cyclic-olefin-copolymer (COC) and Polydimethylsiloxane (PDMS) substrates show hierarchical roughness and complex high-aspect-ratio morphology. Here, they are investigated as superamphiphilic surfaces after plasma etching or superamphiphobic surfaces, after plasma deposition of a thin fluorocarbon film following plasma etching. We show that polymer surfaces etched in oxygen (PMMA, PEEK, COC) or SF6 (PDMS) plasma for few minutes (with texture height< 600nm) exhibit excellent superamphiphobic behaviour, while surfaces treated for longer time show porous-like filamental morphology (filaments several microns height), which is coalesced and stabilized upon wetting, allowing their potential long-term use. Superamphiphobic / amphiphobic behaviour is observed in all cases.