Self-healing core-shell nanofibers for corrosion protective coatings for offshore structures

Protective coatings are used as a corrosion mitigation strategy in many industries. However, damages on transport, installation, and during the service life can expose the metal, leading to failures. Self-healing materials can address this issue by recovering their properties and functionality post-damage. Herein, it was developed an extrinsic self-healing coating by incorporating core-shell nanofibers obtained by coaxial electrospinning. Overcoming the non-spinnability of organosilane compounds, a one-trigger component healing agent was achieved. Additionally, scalability limitations for self-healing coatings were defeated by implementing a viable technique for large-scale structures - Spray painting. The final protective and healing behaviour was investigated by electrochemical and salt spray tests. Following damage, the immediate healing response reached 97.5 %, initiated solely by water. Low capacitance values for the developed coating indicated a robust protective barrier. Furthermore, the self-healing coating efficiently protected steel from corrosion in the salt spray test. The results obtained showed a promising future in using core-shell nanofibers to enhance the durability and protective capabilities of coatings for offshore facilities.