Meanwhile, Dr. Paul Armistead, manager of ONRs Polymer Chemistry program is looking for ideas to outwit the offensive critters. One is a flexible coating organisms might try to settle on a ship but wouldnt be able to grip tightly, allowing the organisms to adhere when the ship is in port, but sloughing them off once the ship reached cruising speed. Yet another idea might be found in textured hull coatings, where the very nature of the shape of the coating (i.e., pattern dimensions and surface energies), might be repugnant to the fouling organisms.
Nothing is quite as easy as it sounds, says Armistead. The silicone based paints are fragile and scrape easily, although we are seeking to improve this with research on nano-composite additives. The textured coatings look promising for repelling barnacles, but not other types of foulers. And some of the other coatings were looking at seem to repel the fouling invertebrates, but confound us by attracting seaweed.
Nevertheless, the Navy knows how to stick to things, too. In a recent Broad Agency Announcement (BAA), ONR solicited proposals in basic and applied research in the age-old battle of the barnacle, and is evaluating those proposals now. Well keep you posted.