An Overview of Epoxy Resins as coating to protect metals from corrosion

Abstract

Any structures of metal, which are used in construction work, must be qualitatively protected from the external environment, more precisely, from the development of corrosion. Under the influence of the environment as a result of corrosive processes, the metal loses its properties. The presence of corrosion reduces the service life of any equipment in production, it worsens the quality of products. To solve the problems of increasing service life and providing chemical protection of metal, which is made of equipment, constructions, and structures, use highly effective anti-corrosion coatings based on epoxy resins. These materials are chemically resistant and provide a barrier that limits the access of corrosive media to the coated surface. Epoxy resins are stable to the action of halogens, acids, and alkalis, and have high adhesion to metals. However, having a complex of positive properties, epoxy resins have significant disadvantages - high combustibility, stiffness, and relatively low physical and mechanical properties, including resistance to impact, due to the limited mobility of inter-nodal sites of the spatial network of polymer macromolecules. Therefore, epoxy is cured with various hardeners and mixed with a variety of fillers (metallic, mineral, and organic), and many other components to reduce the cost of materials and to allow the properties of the resins themselves to be improved in the desired direction. This overview article discusses the basic properties of epoxy resins and the effects of various hardeners, and modifiers on the anti-corrosive properties of epoxy coatings, as well as general applications of epoxy resins and the health risks of their use.