Robust Multifunctional Superhydrophobic Coating via In Situ Micro–nano Growth and Interpenetrating Polymer Networks for Marine Applications

Marine engineering equipment and ships face numerous challenges during long-term operation, including corrosion, biofouling, surface icing, and increased fluid resistance, which significantly affect their safety, durability, and energy efficiency. Superhydrophobic coatings, due to their unique wetting properties, have demonstrated substantial potential in antifouling, anticorrosion, anti-icing, and drag reduction. However, traditional preparation methods often struggle to balance mechanical stability with multifunctional integration. This study proposes a strategy that combines in situ growth of micronano-composite structures with an interpenetrating polymer network matrix, significantly enhancing the bonding strength between the coating and substrate. Moreover, a one-step spray coating process is employed for the rapid fabrication of high-performance superhydrophobic coatings. The coating utilizes carboxylated carbon nanotubes (CNTs-COOH) as a scaffold, with in situ-grown titanium dioxide (TiO2) nanoparticles forming a micronano-rough structure, which is further modified with fluorosilane to reduce surface energy. Simultaneously, the interpenetrating polymer network of fluorocarbon resin (FEVE) and polydimethylsiloxane (PDMS) serves as the matrix, enhancing the coating’s adhesion and structural stability on various substrates. The resulting coating exhibits outstanding overall performance, including hydrophobicity (with a contact angle up to 158°), anticorrosion (protection efficiency of 99.99%), anti-icing (ice adhesion strength reduced by 50%), drag reduction (maximum drag reduction rate of 25.7%), and excellent mechanical durability. Additionally, the coating demonstrates superior self-cleaning and antifouling properties. This study provides a novel design approach for developing superhydrophobic coatings with high durability, suitable for harsh marine environments, offering broad application prospects in ships, offshore platforms, and underwater equipment.