Self-healing corrosion protection film for marine environment

Abstract

This work aims corrosion protection of large marine structures in saline water under realistic conditions of surrounding waves. Self-healing films of Bromobutyl Rubber (BIIR) would normally provide a relatively slow healing, whereas here the additional layer of BIIR with embedded carbon nanotubes (CNTs) used as a heater facilitates self-healing at a much faster rate, which comprises the main unifying topic of this work and is practically relevant. Self-healing BIIR film as the top layer and the attached heater film (CNT/BIIR) as the bottom layer can be prepared by drop casting, painting or spraying of BIIR solution. Joule heating of the CNT/BIIR layer helps to heat the cut site in the BIIR layer up and heal it quickly. BIIR is also a waterproof material and it reveals a successful recovery of a razor-cut crack within a few hours even underwater. CNT/BIIR bilayer coating also passed a corrosion test in saline water and revealed durability being subjected to waves generated by an impeller. Due to these advantages, the proposed method is suitable for corrosion protection of large marine structures.