Triple Dynamic Covalent Network Enabled Self‐Healing MXene /Polybenzoxazine Composite Coatings for Advanced Anticorrosion Applications

ABSTRACT Organic coatings for metal corrosion protection is a core strategy supporting the sustainable and healthy development of modern industrial technologies. Herein, a series of high‐performance anticorrosive MXene/P(VH‐APDS‐EP) nanocomposite coatings with excellent self‐healing based on triple‐effect collaboration of dynamic imine bonds, disulfide bonds, and layered functional MXene were designed and fabricated. Specifically, a benzoxazine monomer (VH‐APDS) containing dynamic imine bonds and disulfide bonds was first synthesized via a two‐step method. Subsequently, P(VH‐APDS‐EP) coatings were fabricated by blending amino groups‐containing VH‐APDS with epoxy groups‐containing epoxy (EP) at various functional group ratios. When the functional group ratio of VH‐APDS to EP was set at 1:1, the resultant P(VH‐APDS‐EP) 1.0 coating exhibited the optimal corrosion resistance and self‐healing performance, with the |Z| 0.01 Hz value of 4.79 × 10 9 Ω cm 2 and self‐healing efficiency of approximately 94.61%, respectively. Subsequently, to further enhance the thermal stability and corrosion resistance of P(VH‐APDS‐EP) 1.0 , novel two‐dimensional MXene were incorporated into P(VH‐APDS‐EP) 1.0 coating matrix. The resultant MXene/P(VH‐APDS‐EP) 1.0 coating exhibited excellent thermal stability and corrosion resistance at a MXene loading of 5 wt.%, with the T d of 352.2°C and the |Z| 0.01 Hz value of 2.51 × 10 10 Ω cm 2 , respectively. Moreover, the composite coating still retained excellent self‐healing performance, achieving a self‐healing efficiency of approximately 95.00%.