Design of a self-stratifying epoxy/thermoplastic polyurethane coating for aerospace applications
Résumé
To functionalize a material’s surface, coatings with diverse properties (adhesive, antibacterial, flame-retardant, etc.) are often required, typically as multi-layer systems. These involve complex application and curing steps, increasing by-products, energy consumption, and processing time, which hinder industrial efficiency in aeronautics and raise environmental concerns. Additionally, interlayer adhesion failure and aging can cause severe defects, leading to corrosion on airplanes. Reducing the number of layers while maintaining or enhancing performance is crucial. Self-stratifying coatings offer a promising solution by forming multilayer structures in a single step, optimizing adhesion and surface properties in one pot application and curing step. Each layer serves a distinct role: the bottom ensures adhesion and protection, while the top provides aesthetics and environmental resistance. This study replaces a two-layer epoxy/polyurethane (PU) system for aerospace applications with an eco-efficient self-stratifying epoxy/thermoplastic polyurethane (TPU) coating. The design, stratification process, challenges, and full coating characterization are discussed.
