Epoxy primer coating filled microcrystalline cellulose treated with silane coupling agent on metal substrate / Mohamad Hafizie Abd Kudus

In this study, epoxy resin was successfully incorporated with microcrystalline cellulose (MCC) in the production of the primer coating on metal substrate. Various sonication times were applied for the purpose of determining the ideal sonication period that provides the best barrier performance. The MCCs were also treated with various loadings of 3-Aminopropyltriethoxysilane (APTES) in order to improve the mechanical and corrosion resistance properties. Fourier Transform Infrared (FTIR) Spectroscopy analysis was carried out to examine the chemical interactions and diffusion between MCC, APTES, and epoxy resin. The coating's mechanical attributes were assessed using pencil hardness testing. It was discovered that at 30 minutes of sonication had enhanced the coating materials' hardness to the optimum level of 5H. Moreover, there is an increase in hardness from 5H to 6H with the addition of 7% and 9% of APTES respectively. As of immersion test, after nine days of immersion in a 5% sodium chloride (NaCl) solution, the ideal sonication period was found to be at 30 minutes, with no corrosion occurring aggressively and no flaking or blistering appears on the coating. The mechanical strength and anti-corrosive qualities of the primer coating were eventually enhanced by the addition of MCC modified with APTES. The addition of APTES had improved the interaction between MCC and epoxy, hence achieving better compatibility and promoting a uniformly dispersed MCC throughout the epoxy resin matrix. The Tafel polarization results found that the addition of APTES up to 9% gave the lowest corrosion rate at 0.004 mm/year and the highest polarization resistances at 198.69 kꭥ. This is explained by the fact that enough MCC-APTES can serve as a physical barrier and obstruct the paths used by corrosive species to diffuse. Therefore, the MCC-Epoxy treated APTES coupling agent proof has great potential in inhibit the corrosion properties of epoxy primer coatings.