A new hybrid silicone-based antifouling coating with nanocomposite hydrogel for durable antifouling properties

A series of hybrid antifouling coatings consisting of silicone elastomer and nanocomposite hydrogel were successfully prepared. The morphology of the hybrid coatings and the silver nanoparticles (AgNPs) embedded into the coatings were studied by SEM and TEM. The pure silicone coating showed a relatively flat morphology. Smooth spheroidal aggregates self-assembled by hydrophilic polymer with a diameter of 4–14 μm appeared when the polymer chains were introduced. However, with increasing of AgNPs the spheroidal aggregates were gradually covered with a thin silicone film and were firmly embedded into the coatings. The glass transition temperature of the hybrid coatings measured by DSC technique showed that the silicone elastomer and the hydrogel matrix formed interpenetrating polymer networks (IPN). The static water contact angle of the hybrid coatings with different amount of the hydrophilic polymer chains before and after being immersed into water was also measured. Furthermore, these hybrid coatings showed good antimicrobial performance for Escherichia coli and anti-algae property. The result showed that the SH-0.25-1.5 sample could almost kill 100% E. coli. Compared with the control sample, the settlement of the Phaeodactylum tricornutum, Navicula torguatum and Chlorella on the surface of SH-0.25-1.5 sample decreased approximately 37%, 37% and 52%, respectively. The antifouling performances of the hybrid coatings were examined by field tests in South China Sea and the result showed the hybrid coatings with nanocomposite hydrogel exhibited good antifouling property. These hybrid coatings have promising applications in marine antifouling coating and interfaces of biomaterials.