Abrasion-Resistant Layered Superhydrophobic Coatings: Fabrication, Performance Evaluation, and Mechanistic Analysis...

Superhydrophobic coatings are regarded as a promising passive anti-icing strategy; however, their practical engineering application, particularly in electrical insulation, is severely hindered by the performance deterioration caused by mechanical damage and a lack of theoretical understanding of microscopic ice adhesion mechanisms. In this study, a layered polymer composite coating was designed to resolve the trade-off between abrasion resistance and low ice adhesion. The chemistry of the coating relies on a synergistic "primer-topcoat" design: the primer consists of an epoxy resin matrix chemically modified by amino silicone oil to lower its surface energy and improve toughness, while the topcoat features hierarchical SiO₂ clusters functionalized with hexamethyldisilazane (HMDS) and silane coupling agents. This architecture was fabricated via a controllable layer-by-layer spraying method. Systematic investigations revealed that the hierarchical micro/nanostructure, composed of microscale protrusions and nanoscale SiO₂ clusters, provides excellent superhydrophobicity (contact angle of 155.2°, sliding angle of 2°). Crucially, the crosslinked polymer network and stable siloxane (Si-O-Si) covalent bonding ensure that the coating maintains its functionality after a cumulative sand impact of 3 kg, demonstrating superior mechanical durability. Furthermore, differentiated theoretical models for ice adhesion in Cassie-Baxter and Wenzel states were established based on intermolecular interactions, identifying that maintaining a stable Cassie-Baxter state is key to reducing adhesion. This study offers a robust approach to balancing functionality and durability in polymer composites through synergistic structural design, providing both a scalable fabrication strategy and a quantitative theoretical framework for understanding interfacial ice adhesion.