Bio-based polybenzoxazine superhydrophobic coating with active corrosion resistance for carbon steel protection

A bio-based benzoxazine, synthesized from cardanol, stearylamine and paraformaldehyde, was utilized to develop a superhydrophobic polybenzoxazine double-layer coating with active protection for carbon steel. This double-layered coating consists of an active anti-corrosive primer and a superhydrophobic topcoat. Halloysite nanocontainers with 2-mercaptobenzimidazole were embedded in the primer to achieve active corrosion resistance. The superhydrophobic topcoat constructed of low-surface-energy polybenzoxazine and amine-modified silica nanoparticles can acquire reinforced passive anticorrosive barrier. The durable double-layer coating could still maintain its superhydrophobicity, even after 60 days of treatment at -20 degrees C or 100 degrees C, or 100 cycles of sandpaper abrasion. More importantly, the electrochemical measurement results indicated that the polybenzoxazine superhydrophobic coating maintained outstanding anti-corrosion performance during 90 days immersion in NaCl solution.

Automated summary

A bio-based benzoxazine synthesized from cardanol was used to develop a superhydrophobic polybenzoxazine double-layer coating, consisting of an active anti-corrosive primer and a superhydrophobic topcoat for carbon steel protection. The coating showed outstanding anti-corrosion performance after exposure to extreme temperatures and abrasion, maintaining its superhydrophobicity even after 60 days of treatment. Additionally, electrochemical measurement results indicated excellent corrosion resistance after 90 days of immersion in NaCl solution.