Evaluation of the wettability of prepared anti-wetting nanocoating on different construction surfaces

Abstract

Generally, the major problems of moisture damage are caused by wetting, and particularly in construction, which has led to extensive research for the production of hydrophobic (anti-wetting) coatings. The aim of this research is to prepare an anti-wetting (hydrophobic) nanocomposite coating for different construction surfaces (ceramic, brick and gypsum). Hydrophobic nanocomposite coating was synthesized using electrospinning technique. Polymethyl methacrylate and polystyrene (PS) solutions were prepared in different ratios and then separately reinforced with ZrO2 and ZnO nanoparticles. Contact angle, surface roughness, surface free energy and weathering effects were calculated for all specimens after being coated. All previously selected materials surfaces showed superhydrophobic and hydrophobic properties. The best results were obtained on ceramic surfaces after coating with PS/ZrO2. The water contact angle was 153° while the surface roughness was 0.491 µm and also showed the lowest surface free energy which was 5.5 mJ/m2. Weathering conditions tend to decrease the values of contact angle and this is due to the environmental effect of the weathering but they still have their hydrophobic properties. SEM test was used to determine the surface morphology and nanoparticle size for ceramic surfaces coated with PS and nano-ZrO2.

Keywords

• anti-wetting
• contact angle
• nano-zirconia
• nano-zinc oxide
• surface coating