No abstract

Rheological and mechanical comparative tests of the new AquaSun antifouling sol-gel coating coated on shipbuilding steel compared to a commercial silyl acrylate antifouling topcoat containing cuprous oxide and copper pyrithione show further evidence of the practical viability of this multifunctional coating for the protection of the immersed surfaces from biofouling. AquaSun is a less rigid or less viscous material than commercial topcoat, but more adherent to the steel substrate. The reason is linked to its lower viscosity and lower stiffness thanks to which it is able to adapt better to the steel surface through chemical bonds between the silanol groups in the organosilica sol and hydroxyl groups at the surface of steel. These results support further investigation of AquaSun as ecofriendly antifouling paint.

Biopolyesters, pure and mixed with a compatibilizer, are exposed to UV-C radiation in the interval 4-32 h. UV-C rays act as germicides and antibacterial on biomedical materials. The mechanical and physical characterization tests have shown how all the materials, pure and mixed, undergo UV-C photodegradation even if in a different way. The change in the structural order of the polymer, the embrittlement, and the change in the surface wettability of the water/blood is lower in the blend than in pure polymers. This is thanks to the cross-linked structure of the mixture, which is more thermally stable, mechanically resistant, and more hydrophobic than the individual components.