Novel eco-friendly antifouling coatings
A new study presents self-renewable amphiphilic coatings with low water swelling and excellent biofilm prevention properties.
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Amphiphilic antifouling coatings have the potential to revolutionise the field of eco-friendly antifouling coatings, which are still beset by the drawbacks of instability, complex procedures and water swelling. Researchers have constructed seawater-triggered amphiphilic coatings with self-renewable capabilities in seawater via the facile casting of a physical mixture of a hydrolysable polymer (PTMH), hydroxyl-terminated polydimethoxysilane and an isocyanate crosslinker. The hydrophilic chain is generated in situ from PTMH at the coating/seawater interface and thus ultimately mitigates its seawater swelling.
Excellent biofilm prevention capability
The hydrolysability of PTMH and the degradation of the urethane crosslinking bond endow the coating with self-renewable properties. Owing to the appropriate hydrolysis rate of PTMH, its water absorption is lower than 3 wt% for 30 days of seawater submersion. According to the researchers, the biofilm prevention capability of the coatings is excellent, outperforming that of polydimethoxysilane-based polyurethane and self-polishing polymers in real sea conditions.
The study has been published in Progress in Organic Coatings, Volume 175, February 2023.