Control of Nanotexture and Wetting Properties of Polydimethylsiloxane from Very Hydrophobic to Super‐Hydrophobic by Plasma Processing

Abstract

Oxygen plasma processing of thermally cured PDMS films results in controlled surface nano‐texturing and wettability. Such treatment of thermally crosslinked PDMS produces spontaneously formed wavy structures on the surface with high nano‐scale amplitude and with periodicity of a few 100 nm. With increasing plasma treatment duration, roughness increased while periodicity decreased, resulting in surfaces of enhanced surface area exploited for the enhancement and control of surface hydrophobicity when followed by Fluorocarbon (FC) film coating of the PDMS surface. We achieved hydrophobic surfaces and super‐hydrophobic surfaces. The mechanisms responsible for the plasma‐induced PDMS surface nanotexturing are discussed, and the variations of the wetting properties have been explained using the Wenzel or Cassie‐Baxter models.

Modeling of Charging on Unconventional Surface Morphologies of PMMA Substrates During Ar Plasma Etching

“…For example, it affects wetting and optical properties of surfaces, [4,5] the adsorption of proteins on surfaces, [6,7] and the cell adhesion and growth. [8,9] The importance of roughness motivated several studies on plasma induced surface roughness of polymeric substrates; [10][11][12][13][14][15][16][17][18][19][20] the focus was on recipes eliminating or producing roughness and on the mechanisms of roughness creation and evolution.…”

Fluorocarbon plasmas for nanotexturing of polymers: A route to water-repellent antireflective surfaces

“…Plasma etching processes have been reported to be effective in inducing a texture on the micro/nano-scale on polydimethydisiloane (PDMS) [6,7], polyethylene (PE) [8], among others, and generally they are fast and easy methods compared to lithographic approaches or deposition of structured coatings. In our previous work CF 4 /O 2 RF plasmas were utilized to roughen and fluorinate polystyrene and under optimized conditions they were proved to be effective in obtaining in one-step superhydrophobic slippery surfaces.…”

The Fracture of Plasma-Treated Polyurethane Surface under Fatigue Loading

“…Detailed analysis of structural-mechanical properties of the treated surfaces (roughness, fractal and wave properties, elastic modulus) and the cross-sections of the modified layer are given in the work [19]. In particular, the elastic modulus of the surface, determined by the AFM nanoindentation, increases with the plasma energy and fluence and was 20 MPa for the untreated PU, 125 MPa (PIII 1-16), 254 MPa (1-17) and 1900 MPa (3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17).…”

“…Treatment of soft polymer leads to the formation of a pronounced wrinkled texture on the surface [15], the peculiarities of surface texture affect the antibacterial properties of the coating [16,17]. The wrinkling phenomenon is related with the loss of stability of the hard layer on the soft substrate due to thermal-induced deformation [18].…”