New application success for Selektope in silicone-epoxy coating
The development of two-part epoxy resin coatings that harness antifouling properties is gaining importance as biofouling challenges increase across the global maritime fleet.
Advances made in epoxies – commonly known as ‘hard coatings’ – are increasingly satisfying the need to offer antifouling protection for hard structures in sea water conditions and vessels operating in harsh environments, in ways that satisfy commercial demands as well as applicable environmental standards.
American paint specialist Wearlon, part of Plastic Maritime Corp., and I-Tech AB of Sweden have recently been conducting work on the development of an epoxy-silicone coating with antifouling properties through the addition of the unique, bio-repellent active agent Selektope with one of the Wearlon silicone-epoxy coatings. Trials, carried out over a period of 19 months, indicate that a commercially-viable ‘hard’ coating that also offers superior antifouling performance is within reach.
Selektope, chemically known as medetomidine and registered by I-Tech AB (Interphase Technologies), is an organic, non-metal compound that is usually used in SPC systems. It is very efficient at preventing barnacle fouling when included in marine coating systems used to paint and protect ocean going vessels, particularly during extended idle times and at elevated water temperatures. Its first-of-its kind mode of action prevents barnacle fouling by temporarily hyper-activating the swimming behaviour of barnacle cyprid larvae, making it impossible for them to settle on a wetted hard surface. It is characterized by high efficacy at extremely low concentrations (0.1-0.3% w/w) and its ultra-low leaching offers paint manufacturers the flexibility to boost copper-based paint formulations or replace copper completely.
Whereas silicone-epoxy systems offer abrasion resistance and easy to clean properties, they still have limitations when exposed to sea water at static conditions. The addition of Selektope enables highly innovative coating systems to be developed and, as such Wearlon has trialled the inclusion of Selektope in its Wearlon Super F-3M range to develop an abrasion-resistant coating with boosted antifouling properties. The coating is expected to be particularly effective in areas where high-wear is likely.
The trialling of the Wearlon epoxy-silicone product containing Selektope was conducted at I-Tech’s test facility on the west coast of Sweden.
By Jake Frith
