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<P>Phase I research seeks to improve production efficiencies at shellfish and finfish farms by solving the biofouling problem through the use of novel soy-based polymers. The proposed non-toxic approach to prevent biofouling of aquaculture gear will improve production efficiency, and thus increase competitiveness of aquaculture in the United States. Eliminating costs associated with cleaning or changing gear used for growing shellfish and finfish by application of the proposed non-toxic antifouling technology will increase profitability of these farms. Improved animal health will result from clean nets and cages through better flow of nutrients and waste products. Most importantly, this research will provide an alternative to copper, the primary antifouling agent relied upon globally for farming finned fish by developing a non-metal-based, non-toxic antifouling product that is environmentally safe and protects aquaculture species from exposure to heavy metals commonly used in anti-fouling products. </P>
<P>NON-TECHNICAL SUMMARY: The objective of the proposed research effort is to develop low-cost, non-toxic, soy-based polymers as vehicles for ePaint photoactive antifouling technology. Phase I research investigates the feasibility of synthesizing soy polymers as water-based emulsions and assessing their utility as photoactive biofouling release coatings. This approach, if successful, will result in an affordable, non-toxic means for controlling biofouling, a serious problem for aquaculture worldwide. A soy-based, non-toxic solution for controlling biofouling on aquaculture gear will 1) improve aquaculture efficiencies; 2) improve the health of farmed species; 3) increase demand for US grown crops (soy); and 4) replace current toxic methods for biofouling control. </P>
<P>APPROACH: The success of this Phase I effort will be determined by the degree to which novel soy-based photoactive coatings deter biofouling after three months exposure in New England waters. Maximizing soy oil content is the primary objective of Phase I polymer synthesis. Soy polymers will be used as low-cost, non-toxic binders for photoactive biofouling release coatings. Target soy oil concentration by weight wet resin is 60%.Biofouling release coating formulation involves blending soy-based polymers with polyhydroxylated filler, titanium dioxide nanoparticles and catalysts in varying rations. The combination of materials will afford chain cleavage in the presence of light-generated hydrogen peroxide resulting in the release of biofouling.Concentrations of titanium dioxide nanoparticles and catalysts will be varied to optimize hydrogen peroxide concentration and self-polishing properties of the coating over time in water. Optimized formulas will generate H2O2 concentrations ≥ 1ppm in one hour. Soy-based formulas must flow well with optimal viscosity of 1100 cP, be VOC-free and waterborne. Optimization of coating properties, peroxide generation, and biofouling release by varying ratios of components is the objective in Phase I. Peroxide release rate testing will be performed following ASTM D6642 and the HTP-1 method for measuring peroxides.Coating properties will be optimized for use on aquaculture gear. Soy-based photoactive coatings must form good films on metal, plastic, and composite substrates. Films must be adherent, flexible, mar-resistant, and hydrophobic. Coating properties testing is planned following ASTM Methods D1640, D7334, D2134, D3363, D5628, D4060 and D1894. Biofouling resistance testing will be performed from the docks of the University of Connecticut at Avery Point following ASTM D 6990, "Standard Practice for Evaluating Biofouling Resistance and Physical Performance of Marine Coating Systems." Results from testing will be reported in one interim report, and a comprehensive final report. </P>