Antifouling paints with zinc “tannate”

N. BELLOTTI; M.C. DEYÁ; B. DEL AMO; R. ROMAGNOLI

INDUSTRIAL & ENGINEERING CHEMICAL RESEARCH

American Chemical Society

Lugar: Washington; Año: 2010 vol. 49 p. 3386 - 3390

0888-5885

During the last decade, the necessity of new eco-friendly antifouling pigments was established. Among these new pigments special attention should be paid to tannin and its derivatives. Tannins are synthesized by plants as part of their defense mechanism against the attack of pathogens.  The aim of this work was to study the antifouling efficiency of paints containing zinc “tannate”, in artificial sea water. The zinc “tannate” was precipitated at pH 4 and 8. Insoluble and soluble matrix antifouling paints, with different plasticizers, were formulated and tannins leached from the paints immersed in artificial sea water were determined by the Folin-Denis assay for polyphenols. The antifouling action of paints was assessed in a natural sea water environment. The results showed that the leaching rate of tannin from insoluble matrix paint decreases, reaching a constant value after 25 days of immersion. In the case of the soluble matrix paints, a lesser amount of tannin was leached depending on the tannin and on the plasticizer employed. The results in natural sea environment depend on the matrix and on the plasticizer employed.