Bioinspired self-stratification fouling release silicone coating with strong adhesion to substrate

Silicone-based fouling release coatings (FRCs) are considered to be one of the promising eco-friendly antifouling technologies, while traditional silicone-based FRCs generally have poor adhesion to substrate. In this work, we developed a self-stratification silicone-based mussel-inspired bionic FRCs with strong substrate adhesion and good fouling-release ability. The coatings are silicone-based polybenzoxazine synthesized by natural phenolic derivatives (eugenol, urushiol and pyrogallic) and poly-(dimethylsiloxane)etherimide, with phenolic hydroxyl groups enriched at the bottom while hydrophobic siloxane groups at the surface. The coatings exhibit strong bonding to various substrates (stainless steel, aluminum, copper, epoxy and glass) under both dry and wet conditions. The maximum substrate adhesion strength of the coating is up to 3.6 MPa (six times greater than that of polydimethysiloxane (PDMS)) under dry condition and 3.0 MPa (five times greater than that of PDMS) under wet condition. While this silicone-based self-stratification fouling release coating addictive with a low modulus and surface energy as PDMS does, it showed an enhanced anti-bacteria and anti-algae adhesion abilities. The results indicate a great potential for the application of this concept of developing the fouling release marine coatings with high substrate adhesion.