Functionalization of aerosil, titanium dioxide and diatomaceous earth powders by wetting with a low surface energy agent, and study of their properties

Abstract

The conditions for functionalization of micro- and nanopowders of aerosil, titanium dioxide and diatomaceous earth by wetting them with a liquid hydrophobic agent (tetraethoxysilane) and giving them fobno/philic properties are investigated. Using infrared spectroscopy, derivatography, scanning electron microscopy, and ξ-metry, the mechanism of tetraethoxysilane interaction with the surface of these powders and their morphology were studied. All powders thus modified are characterized by a non-homogeneous distribution of particles with different aggregation levels: predominantly micrometer-sized particle population (diatomaceous earth), micrometer-sized formation combined with nanoclusters (aerosil, titanium dioxide). Diluted suspensions of functionalized powders in fluorinated varnish were used for hydrophobization of glass, aluminum, and steel surfaces. The highest value of the water wetting edge angle (156°) was observed for aluminum coatings obtained using a composition containing functionalized aerosil.