Abstract: The invention provides a marine antifouling coating composition comprising a tributyltin acrylate coresin in the range of from about 10% to about 25% by weight, a tributyltin polysiloxane coresin in the range of from about 2% to about 20% by weight, at least one filler in the range of from about 10% to about 50% by weight and a solvent in an amount of from about 20% to about 50% by weight. Preferred tributyltin acrylate coresins comprise copolymers of tributyltin methacrylate monomers and methyl methacrylate monomers.

Abstract: A marine antifouling coating composition comprises an acrylic resin such as methyl methacrylate in the range of from 6 to 20% by weight, a polysiloxane having substituted thereon tributyltin moieties that are toxic to marine organisms. The polysiloxane is in the range of from 7 to 25% by weight. The acrylic resin and polysiloxane are dissolved in a solvent in the range of from 18 to 52% by weight with the balance of the composition in the range of from 10 to 65% by weight being primarily conventional marine paint and toxicant agents for augmenting action of the tributyltin polysiloxane. Copper or copper salts that are effective for inhibiting growth of marine organisms and facilitating release of toxins can also be included.