Amphiphilic Janus F-SiO2-NH2 particles modified waterborne epoxy coating with excellent anti-corrosion performance

In this work, amphiphilic Janus F-SiO 2 -NH 2 particles were prepared through step-by-step modification of SiO 2 particles inlaid in and released from paraffin microspheres by fluorosilane and aminosilane respectively, and further modified waterborne epoxy (WEP) coating. The morphology, structure, composition, and surface wettability of the prepared particles as well as the mechanical properties and corrosion resistance were investigated. The results indicate that the modified coating gained the improved mechanical properties and anti-corrosion performance. Electrochemical impedance spectroscopy tests show that after immersion in 3.5 wt% NaCl solution for 15 days, the impedance modulus at low frequency of F-SiO 2 -NH 2 modified WEP coating was above 10 6  Ω∙cm 2 , two orders of magnitude higher than that of WEP coating. The amphiphilic Janus F-SiO 2 -NH 2 particles not only improved the interfacial compatibility and penetration resistance through the good dispersibility, hydrophobic groups and cross-linking with epoxy resin matrix, but also oriented adsorbed on steel surface to form protective hydrophobic layers. This work provides a simple design approach for constructing highly corrosion-resistant waterborne coatings, which has a certain promoting effect on the development of environmentally friendly high-performance anti-corrosion coatings.