Verification of the Influence of Particle Shape on the Chemical Resistance of Epoxy Coating and Use of Waste Glass as the Filler

Abstract

The use of suitable secondary raw materials as fillers in progressive, protective agents primarily intended for horizontal concrete construction is very effective not only from the ecological but also from the economic point of view. The impact of using various types of waste glass as fillers on the mechanical parameters of epoxy coatings was experimentally verified. Assessing the dependency of the coating’s chemical resistance on the shape of the used filler’s particles was the main aim of the performed research. A solvent-free epoxy suitable for a chemically aggressive environment was selected for the experiment. These were epoxy coatings filled with a micro filler based on raw materials such as glass flakes and silica flour. Three tested formulations containing fillers with different particle shapes and characteristics were exposed to H2SO4, HCl, CH2O2 and NaOH at concentrations of 5% and 30% and evaluated after 60, 90 and 120 days. The chemical resistance assessment was carried out not only visually but also using a scanning electron microscope (SEM). Thanks to the use of the waste glass as a coating filler, tensile properties and hardness improved, and its use did not negatively affect the chemical resistance and adhesion of the epoxy coatings. It was found that the shape of the filler particles influences the resistance of the coating against a chemically aggressive environment. The epoxy coating containing pre-treated waste windshield glass (shards) showed even better properties than the reference coating.