Abstract
Several experimental and commercially available coatings were tested to evaluate their antifouling performance in unfiltered, natural seawater. The coatings were applied to replicate sets of test coupons with one set exposed to near static flow conditions and the other set exposed to fast currents of ~2.5 knots. All of the coupons experienced fouling, but some fouled more heavily than others. A critical finding of the test campaign included the importance of the application technique to achieving a consistent surface and good adhesion. Some coatings may be ruled out for further study due to the fragility of the coating. Other coatings will require additional research to achieve scale-up of production and application onto larger and geometrically complex surfaces. At this time, none of the experimental coatings significantly outperformed commercially available coatings, but some of the novel coatings did achieve equal performance and may be able to improve upon those results.
Summary
Pacific Northwest National Laboratory (PNNL) conducted tests to assess the efficacy of various coatings designed to prevent biofouling. Sandia National Laboratory (SNL) and its partners provided coupons with various antifouling coatings and these coupons underwent time-series exposures under controlled laboratory tests at PNNL’s Marine Sciences Laboratory in Sequim, Washington. The PNNL team assessed the coupons to evaluate the extent, timing, and type of fouling buildup that occurred. A companion report from SNL provides details about each coating, including the intended mechanism of protection and the methods of fabrication and application onto the coupon surfaces.