Due to the regulations of toxic biocidal products in marine environments, the development of nontoxic antifouling (AF) coatings has become required. The development of nontoxic antifouling formulations implies the use of ingredients (such as: polymers, additives and pigments) that are devoid of toxicity towards marine environments. In this regard, erodible coatings, based on biodegradable polymer, are used to respond to this problem. Recently, polyurethane (PU) has been adopted into antifouling coating due to its ability to migrate the certain functional groups which resist the attachment of fouling. Biodegradation of PU can accelerate the erodible properties which ultimately improve the antifouling properties. In this study, a series of biodegradable PU coatings was formulated by tuning biodegradable polyol. The antifouling performance was evaluated after certain intervals.
Self-polishing coatings (SPC) are widely being used in marine structures to protect metals from fouling. After restrictions on using toxic metals, coating industry are seeking environmentally-friendly SPC coatings that maintain their performance over extended periods. Unfortunately, most of the commercial SPC coatings contain different toxic materials, besides their performance is inadequate to prevent fouling under adverse conditions. The main mechanism of SPC coating is to facilitate the continuous renewal of the surface and the release of active compound via a hydrolysis reaction or an ion exchange reaction with seawater. In this study, polyurethane (PU) SPC coatings were synthesized by in-situ polymerization using biodegradable polyol. The polishing rate of coating was determined from the reduction in dry film thickness after artificial seawater immersion under a dynamic condition. The fouling resistance of coatings was considered after certain interval.