When a metal surface interacts with its environment, corrosion occurs spontaneously and irreversibly. This results in significant financial losses, the failure of critical environmental issues, and component issues. One of the biggest issues facing industries around the world is corrosion avoidance. The most popular method for enhancing the longevity of metallic alloys is by coating them with protective compounds, such as paints, resins, or those made of ceramic materials. However, coatings made entirely of ceramic materials are likely to be porous and to experience intrinsic stress-induced cracking, posing limitations on coating thickness [1]. As a result, organic-inorganic hybrids have been developed to overcome conventional coatings drawbacks and create an effective and long-lasting corrosion protection system for metallic surfaces. The aerospace/aircraft industry, where high service temperatures are necessary, uses epoxy resins most frequently for resin-based composites. These resins should offer high thermal stability, convenient processability, good mechanical qualities, and chemical resistance. The author cited, that the hardener structure influences the final properties of the cured polymer matrix in equal measure to the epoxy resin, new hardeners for polyepoxides for composite materials are found to the special relevance in this situation [2]. Epoxy resin materials are frequently used in industries for their excellent mechanical and chemical characteristics, low cost, and strong binding power. Recently, epoxy resins were also introduced as an adhesive to enhance the robustness of superhydrophobic coatings [3]. Epoxy coatings are thermosets that perform exceptionally well in terms of strength, hardness, heat, and adhesive capabilities, making them the perfect choice for several bonding, structural, and protective applications. Epoxies are one of the most frequently used commercial barrier coatings to stop rust from metal surfaces, which can help prevent significant financial losses. However, the protective coating can sometimes fail after protracted environmental factors or mechanical stress, exposing the metal surface [4]. To endure these severe standards, new kinds of cross-linkers to improve efficiency author were designed, two-component epoxy coatings [4]. Jia and Hong reported anticorrosion properties of epoxy-silica and organic coating, the author described that inorganic nanoparticles such as silica and zinc oxide improve the anti-corrosive performance of hybrid coating to prevent the entry of air and moisture and protect glass from corrosion [5, 6]. Tian and their co-worker reported a unique composite coating process with biobased polyurethane and olefine wax as curing agents [7]. Various method for curing epoxy is known, Pulikkalparambil and co-workers reported the double container inner covering produced in the current study that self-heals when exposed to daylight. Silica nanoparticles were employed as a container for the UV initiator, while HNTs served as a nanocontainer to enclose bio-based epoxy resin [8]. Zhang and his group reported a multipurpose epoxy resin composite coating using a sequential coating process, graphene, and α-alumina. The fillers block the corrosive media efficiently, improving the epoxy composites' corrosion protection function. The entire corrosion procedure is monitored by electrochemical reaction [9]. Jayabharati and Jothramlingam developed imidazole diamine epoxy coating for corrosion protection, and various applications of epoxy coating are known in the literature [10–12] as hardeners are costly and curing time variable [10–21].
In previous work, we used solid hardener orthophenylene diamine and phenyl hydrazine as curing agents in the oven in acetone at high temperatures. The problem was with this method (a huge amount of hardener in acetone, and curing was performed in the oven at high temperature) [22]. To overcome this difficulty according to literature, the presence of functional group interaction in solvent affects the percentage of the solid hardliner and curing time. According to the literature, the solvent should have hydrogen bonding interaction with the hardener to enhance the curing time and parentage use of the hardener. In the present study, we used 2–4 dinitro phenyl hydrazine as a solvent curing agent in an acetone/aniline (1:1) ratio, and acetone and results are discussed below.