Polyurethane Coating Catalysts for Ambient Cure Concrete Protective Coating Layers: A Comprehensive Review Abstract: Concrete structures are susceptible to various forms of degradation, necessitating the application of protective coatings. Polyurethane (PU) coatings, renowned for their durability, flexibility, and chemical resistance, are widely employed for this purpose. Ambient cure PU coatings, particularly advantageous for on-site applications,...