Multifunctional and robust composite coating with water repellency and self-healing against marine corrosion

Co-working by lotus-leaf effect and self-healing shows a great potential against marine corrosion as it could form a barrier capable of water repelling and microdefect healing on the substrate. We developed a firm and self-healing superhydrophobic coating (SHC) technology, in which carbon steel substrate was first coated with fluoroethylene vinyl ether resin/polycaprolactone (FEVE/PCL) hybrid resin, and then sprayed with SiO2. Results showed that the hybrid resin could strengthen the interface between the SiO2 layer and the substrate and could heal microdefect due to the thermal exudation effect of PCL, and consequently form a corrosion barrier. The SHC exhibited great water resistance, stability, and durability. This dual-layered coating performed excellently in corrosion prevention. With the thermal exudation effect of PCL, the dual-layered coating could quickly recover its superhydrophobicity and corrosion resistance under thermal stimuli, making it possible to protect metal substrate persistently. Therefore, this approach provides an easy technique against marine corrosion with water repelling and scratch-healing ability, and shall be promising for long-term corrosion protection. (C) 2022 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.