Siloxane-polyurethane fouling-release coatings based on PDMS macromers

Marine biofouling is the accumulation of organisms onto surfaces immersed in sea water. Fouling of ships causes an increase in hydrodynamic drag which leads to performance issues such as increased fuel consumption and a reduced top operating speed. Fouling-release (FR) coatings are one way that paints have been used in combating biofouling by allowing for the easy removal of settled organisms. Traditional FR coatings are silicone elastomers which are soft, easily damaged, and require a tie coat for adhesion to marine primers. Siloxane-polyurethane FR coatings have shown promise as FR coatings, providing enhanced durability and toughness, better adhesion to marine primers, and comparable FR performance to commercial coatings.;Siloxane-polyurethane coatings based on PDMS macromers were prepared and thoroughly assessed for fouling-release performance. The coatings were shown to have comparable fouling-release performance to commercial fouling-release standard coatings in laboratory high-throughput analysis. Static immersion field testing illustrated the potential of these coatings to serve as fouling-release coatings where removal of biofilms and barnacles was achieved for up to nine months. Underwater hull cleaning of these coatings demonstrated their durability in both the marine environment and when subjected to aggressive physical cleaning. Pigmentation of siloxane-polyurethane coatings illustrated potential for the coating systems to serve as opaque coatings without compromising their fouling-release performance. Additional polymer architectures were explored which demonstrated additional experimental space where siloxane-polyurethane coatings can be further developed into potentially higher performing systems.;In general terms, this research demonstrated the basic efficacy of siloxane-polyurethane fouling-release coatings based on PDMS macromers. The results presented herein illustrate the potential of these systems to add value to the commercial fouling-release coatings which are currently available.