Pre-adsorbed Selektope®. Creation of a new carrier system for Selektope® via pre-adsorption on Zinc Oxide for enhanced antifouling performance

Over the past five years, I-Tech’s team of R&D scientists have discovered new ways in which the first-of-its-kind biocide, Selektope® can be introduced to marine antifouling coatings in combination with other biocides with little or no effect on formulation chemistry or performance. 

Although the controlled release of Selektope in SPC coatings has been proved successful with multiple products commercialised to-date, recent I-Tech R&D efforts have focussed on obtaining proof of concept that pre-adsorbing Selektope on the carrier compound zinc oxide (ZnO) improves coating stability, reduces the risk of viscosity increase and improves the biocidal leaching for sustained antifouling performance.

By pre-adsorbed we mean adsorbing Selektope on the surface of a pigment from a Selektope solution, followed by separation evaporation of the solvent to obtain a powder additive of Selektope adsorbed on the surface of the pigment. This pre-adsorption process is completely external from the actual paint manufacturing process. Tests conducted to-date show strong results and I-Tech is continuing work in this research field.

An additional proof of concept was obtained for the addition of Selektope pre-adsorbed on ZnO to foul release coatings. If Selektope is not properly incorporated into a foul release coating matrix it will leach to the surface of the coating too fast. Therefore, this new method of introducing Selektope pre-adsorbed to ZnO could open a route for the use of the biocide in these types of coating system. Another major benefit is that the addition of Selektope, pre-adsorbed on pigment particles does not require fundamental reformulation. By contrast, it is even possible to add it into ready-made paint. Positive test results have been obtained to-date and further testing is underway in this research field.