Performance and effectiveness of non-stick coatings in seawater

Several non-stick coatings mainly based on silicones were tested under laboratory and field conditions in regard to their toxicity and their influence on the settlement of cyprid larvae (Balanus amphitrite). The toxicity was very low for most of the coatings. The antifouling properties were evaluated in exposure trials over 6 months at several stations along the German coast. The field trials were performed by stationary exposure and with periodically moved catamarans. The silicon coatings exhibited the best performance and 4 out of 9 of these were highly effective. The adhesion force of barnacles on silicones was substantially reduced in relation to control substrata. The leaching of organotin compounds derived from some of the silicone coatings used was less than, or in the range of, the induction leaching-rates found in organotin-stabilized Formica tubes.