Study On Novel Tin-free Self-polishing Antifouling Marine Coating

Antifouling coatings are the most reliable way to prevent biofouling of immersed submerged surfaces. As concerning the high toxicity of organotin paints, the coatings which do not present environmental risks have become the development tendency. The main objective of this research is to develop an advanced tin-free self-polishing antifouling coating (TF—SPC) being of low surface energy propertity.In respect that the key body of self-polishing coating is the self-polishing copolymer with hydrolysable functions, firstly, polyalkoxysilane grafted by hydroxyl acrylic resin was used to obtain an adhesive with self-polishing and low surface energy properties. The polyalkoxysilane was made by tetrathoxysiliane by hydrolyzed partly, while series of acrylate materials were used to synthetized acrylic resin, then the polyalkoxysilane and hydroxyl acrylic resin were copolymerized to make the result product. Nine pieces of advanced copolymers G-9-1～G-9-9 were ultimately developed by adjusting in series the prescription and techinics of synthesis experiment, whose propertities are excellent: adhensive power is two grade, hardness is H, resistance of impact is 50 Kg·cm, storage time is over 6 months and surface energy lies in 23～32 mJ·m^-2.Then the coatings were prepared by using the as synthesized resin G-9-1 — G-9-9 as the film forming matter, Cu₂O as biocide, zinc oxide as fillings, and nano-SiO₂ as the other antifouling reagent. And the releasing rate of copper ion and the surface energy were measured, the results showed that the optimal property of surface energy is 25 mJ·m^-2, and the tendance of the relasing rate of copper ion becomes stable after immersed 9 days.Using low surface energy hydrolyzed silicic copolymer to improve the static antifouling ability of self-polishing coating is a novel way to develop non-toxic, efficient and economic antifouling coating.