Synthesis of Smart Halloysite Nanocontainers and usage for corrosion inhibitor coatings

The main purpose of the presented thesis is to synthesize and characterize Smart Halloysite Nanotubes for use in anti-corrosion coatings. When we look at the sectors directly and indirectly affected by corrosion, many fields such as aviation, energy, chemistry, food, oil and gas, pharmacy, machinery and civil engineering can be listed. Today, the aviation sector is the leading sector when considering safety and speed factors. With the precautions taken during production and maintenance work, corrosion damage resulting from the harsh conditions in which the aircraft are found has been tried to be prevented. Material selection and finishing processes during the design process are important factors affecting the corrosion resistance of aluminum alloys used in the aircraft body. For this reason, Aluminum 7075 alloy was preferred as the surface. There are two main approaches to applying smart coatings with self-healing properties used for anti-corrosion applications. The first method involves localized repair of the damaged coating by controlled release of polymerizable agents, while the second method requires electrochemical protection of the exposed metallic substrate using corrosion inhibitors stored in nanocontainers. In this thesis study, the second method mentioned above was applied. Within the scope of the study, aluminum alloy was used as the main material, Halloysite nanotubes were used as nano containers, and Benzotriazole (BTA) was used as an inhibitor. The layer-by-layer bonding (LBL) method was applied as an end-stopping system for nanotubes, and Poly(maleic anhydride-alt-acrylic acid) copolymer was synthesized to be used in the LBL method. In addition, the calcination process aims to enlarge the inner diameter of halloysite nanotubes and increase the loading capacity of corrosion inhibitors. After the calcination of the halloysite nanotubes, BTA loading was carried out on the calcined and uncalcined nanotubes, and then the BTA-loaded halloysite nanotubes were synthesized with Poly(maleic anhydride-alt-acrylic acid) copolymer. A study was carried out to improve the corrosion that occurs on aluminum alloy with the nanotubes formed as a result of synthesis. In addition, aluminum alloys were coated with nanotubes and then treated with acid to observe whether they would corrode. The morphology and properties of the nanocontainers were characterized by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). The amount of benzotriazole (BTA) loaded in the halloysite lumen was determined by thermogravimetric analysis (TGA). Additionally, Surface area and pore size (BET) analysis was performed after loading. Dynamic Mechanical Analysis (DMA) was used to follow the dynamic mechanical properties of the nanocontainers. The control of the healing of the defective area exposed to corrosion was illuminated by scanning electron microscopy (SEM-EDX). Within the scope of the thesis, self-healing structures against corrosion made with the use of nano-containers can contribute both nationally and internationally, reduce financial losses especially in the defense industry and other industries, and compete in both our country and the world market by being non-toxic with the use of environmentally friendly polymers. It is considered as the original value of the thesis. Additionally, preventing inhibitor leakage with the layer-by-layer bonding technique increases the success of the system.