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

Abstract

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.