Micelle-Assisted Encapsulation Strategy in Metal-Organic Framework Nanocontainers Enables Durable Corrosion...

Encapsulation is an effective strategy for stabilizing and controlling functional molecules. Although amphiphilic micelles are widely used to host molecular cargo, their intrinsic encapsulation capability remains underexplored for directly confining functional molecules within inorganic or hybrid architectures. Here, we report a hierarchical nanocontainer integrating micelle-assisted molecular encapsulation, ZIF-8 confinement, and SiO₂ interfacial engineering for smart self-healing corrosion protection. Amphiphilic P123 micelles first encapsulate benzotriazole (BTA) in situ and direct ZIF-8 framework growth around the loaded micelles, enabling efficient one-pot inhibitor confinement without a separate post-loading step. A subsequent SiO₂ shell improves structural robustness and compatibility with environmentally friendly waterborne polyurethane (WBPU) while preserving pH-responsive release. Under corrosive conditions, local pH changes trigger BTA release, enabling active inhibition and self-healing at damaged sites. The nanocontainers achieve inhibitor loadings up to 16.2 wt% and pH-dependent release, reaching ~35% at pH 3 and ~32% at pH 10, compared with ~4% at pH 7. Incorporated into WBPU coatings, the composite maintains ~1.4 × 10⁷ Ω·cm² after 39 days in 3.5 wt% NaCl. It also shows a corrosion current density of 3.2 × 10^-9 A cm^-2 and a corrosion rate of 0.0000372 mm year^-1, demonstrating durable protection. This strategy enables high-loading, release-regulated nanocontainers for anticorrosion coatings.