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Vinyl ester prepolymer is produced by the reaction of epoxy resin with acrylic or methacrylic acid containing vinyl groups. Bisphenol A and phenolic epoxy are commonly used. Bisphenol A vinyl ester possesses excellent chemical resistance, while phenolic vinyl ester coatings have outstanding acid and solvent resistance as well as good heat resistance. The polymer is dissolved in styrene monomer; a catalyst and a curing agent are added, and the styrene begins to cross-link with the resin, forming a solid component. If the paint surface is exposed to oxygen in the air, its curing process will be slowed down or even completely halted; therefore, adding a small amount of paraffin can effectively prevent oxygen from reaching the surface, as well as stop the volatilization of styrene during the polymerization reaction. Vinyl esters contract inherently upon curing (to a lesser extent than polyesters), accompanied by an exothermic reaction. Adding glass flakes can absorb this contraction. Vinyl esters are typically two-component coatings that can be applied at room temperature. It can be applied using a two-component paint pump; conventional airless spray pumps can also be used. At 23°C, the canning life is only 40–45 minutes, due to the addition of MEK peroxide, which causes the vinyl ester to begin curing. At the same time, an exothermic reaction occurs, which also accelerates the curing process. To maintain its canning life at 40–45 minutes, a retarding agent can be added during processing at a temperature of 30–40°C. At temperatures as low as 15°C (which is the minimum application temperature for vinyl esters), the amount of MEK must be increased. When adding curing agents and inhibitors, follow the recommendations of the paint manufacturer. To ensure optimal adhesion, concrete and steel must be sandblasted. The steel should have a sandblasted surface quality of at least Sa2.5 (ISO 8501-1), with a roughness value of Rz between 75 and 100 μm. On the concrete surface, an ethylene varnish should be applied first to ensure optimal adhesion for the main system. Vinyl ester coatings cannot be applied to old paint or galvanized steel. Due to its excellent chemical and solvent resistance, vinyl ester coatings are often referred to as the \"solution to problems\" when used on the inner walls of storage tanks. It can effectively resist a wide range of chemicals, including unleaded gasoline. It can be used in sulfur smoke scrubbing systems, brine, drilling mud, and treated water. Vinyl ester coatings have better chemical resistance than polyester coatings; they exhibit extremely strong alkali resistance and slightly stronger acid resistance. It also has excellent high-temperature performance.