Superhydrophobic polysiloxane filament growth on non-activated polymer coatings

Abstract

Superhydrophobic polysiloxane nanofilaments were successfully grown on polymer coatings prepared by conventional emulsion polymerization without the application of any activation step for the first time using methyltrichlorosilane as the silane precursor. Both gas phase reactions under a controlled humidity environment and liquid phase reactions in standard petroleum ether which is open to air were applied during filament growth. Wettability, morphology and transparency of the obtained polysiloxane nanofilaments were characterized by contact angle measurements, scanning electron microscopy and UV-vis transmittance tests respectively. Advancing contact angle values between 166–172° and 157–169° were obtained via the gas phase reactions and the liquid phase reactions, respectively. It was also shown that polysiloxane nanofilaments can be grown on polystyrene coatings prepared by solution polymerization without any pre-activation step via the liquid phase filament growth reaction. It was determined that the presence of hydroxyl groups on a polymer coating is not required for the growth of polysiloxane nanofilaments, and only the formation of a water film having an adequate thickness on the polymeric coating surface is sufficient.