Preparation and Characterization of Cross-linked Fluorosilicone-Epoxy Modified Waterborne Acrylic Resin with Enhanced Water and Corrosion Resistance

To address the poor water and corrosion resistance of traditional waterborne acrylic resins, fluorosilicone-epoxy synergistically modified waterborne acrylic resins (FSiEAs) were synthesized via semicontinuous seed emulsion polymerization with methyl methacrylate, butyl acrylate, and 2-hydroxyethyl methacrylate as main monomers, and 3-(methacryloyloxy)propyltris(trimethylsilyloxy) silane (M3T), 2-(perfluorooctyl)ethyl methacrylate (FMA), and epoxy resin E51 as functional modifiers. Cross-linked coatings (CFSiEAs) were obtained by blending FSiEAs with aliphatic polyisocyanate curing agent HL-2800. FTIR confirmed the successful incorporation of E51, M3T, and FMA. The cross-linking density and water resistance of CFSiEAs first increased then slightly decreased with increasing E51 content. The optimal CFSiEA-5 exhibited maximum cross-linking density, minimum water absorption (4.99%), lowest corrosion current density (2.249 × 10–10 A/cm2), highest |Z|0.01Hz (1.69 × 109 Ω·cm2 after 60-day immersion), and no rust spots after 1440 h salt spray test. This study provides guidance for developing high-performance, environmentally friendly waterborne acrylic coatings with excellent water repellency and long-term anticorrosion stability.