WATER REPELLENT HYDROPHOBIC SURFACES AND ANTI-FUNGAL NANOCOATINGS FOR BUILDING APPLICATIONS

Abstract

The utilisation of nanocoatings have been gaining widespread popularity in the building industry due to their excellent properties. Hydrophobic nanocoatings have displayed exceptional water repellent and self-cleaning effects, and anti-fungal nanocoatings have the ability to slow down the rate of the fungal growth on building materials. These functions can substantially decrease costs, time and manpower due to the reduction in maintenance efforts required, making them well-suited for applications on building materials. This paper aims to prove the hypothesis that silane coated SiO2 spheres with added polymer binders have the ability to enhance the surface hydrophobicity. Varying ratios of chemicals and materials were used and drop coated onto glass and foam concrete substrates. To test the hydrophobicity, the WCA values were compared and water penetration tests were conducted. Water penetration tests were conducted by pouring water into the rilem tubes attached to the foam concrete block and recording the drop in water level at fixed intervals. Extensive experimentation has led to the development of a nanocoating with a WCA of 121°, verifying that silane coated SiO2 spheres nanocoatings indeed has a hydrophobic effect. Surfaces coated with ZnO nanoparticles are suggested to delay the development of fungus, hence this paper also investigates this hypothesis. ZnO nanoparticles and various binders were applied onto clay tiles then placed on an AC ledge. The tiles were closely observed to determine the effectiveness of ZnO nanoparticles on decreasing fungus inhibition. However, a challenge faced was the inability to find an appropriate location which encourages fungus growth.