Novel Use of Waste Fruit-Seeds for Enhancing Anti-Corrosive Performance in Epoxy System

Abstract

Epoxy coating system with enhanced corrosion resistance was prepared. The epoxy resin was used as a base resin and polyamine was used as its hardener. The ashes of Karwand (Carissa carandas) seeds and Pumpkin (Cucurbita pepo) seeds were used to increase the anticorrosive performance of the coating. These ashes were prepared by the method of calcination in a muffle furnace by heating at 800°C for 2 hours. Surface treatment was done to introduce amine functionality to the ash which was confirmed by FTIR analysis. The surface treated ash was then added into the epoxy-amine system at 1%, 3%, 5% (w/w) of the total epoxy-amine coating system. The coating was then applied to mild steel panels by the method of brush coating and was tested for mechanical properties and chemical resistance. The coating was also subjected to the salt spray test for analysis of anticorrosive performance. It was observed that the anticorrosive performance of the coating increases as the concentration of ash in the epoxy-amine system increases. This is due to ash constituents such as ZnO, MgO, Fe2O3, CuO etc. which work either by barrier mechanism or passivation mechanism and prevent corrosion. The scratch resistance and the hardness also increased with an increase in the concentration of ash. This is because the ash in the epoxy-amine system acts as filler in the coating. Also, surface treatment introduces amine functionality which reacts with the epoxy group and tends to increase hardness. Thus, presence of inorganic elements in the ash and surface treatment are prime factors responsible for enhancing corrosion resistance of the system.