New environmentally friendly bottom paints have been developed in Sweden to prevent biofouling on ships’ hulls.
Such fouling can lead to higher fuel consumption and the spread of alien species that do not belong in the local marine environment.
Researchers at Gothenburg University and Chalmers University of Technology have spent nine years developing environmentally friendly and effective anti-fouling paints through a joint research programme called Marine Paint.
According to a statement, the focus has been on a substance called medetomidine, which has proved highly effective against barnacles, which are considered to be the most problematic fouling organism.
To tackle other types of fouling as well (such as algae, mussels, sea squirts and moss animals), the researchers have developed a concept for producing optimised combinations of different anti-fouling agents, or biocides.
The idea behind these optimised blends is to combine many different biocides that are effective against different fouling organisms and adjust the balance between them to eliminate all types of fouling.
To produce the recipes for these optimised blends, the researchers have also developed a model system where they weigh the effect of different biocides on different fouling organisms against their expected environmental risk. The blends are all equally effective but offer different levels of expected environmental risk.
These optimised blends have been combined with high-tech paint systems based on microcapsules made out of a polymer material that slowly release the biocides from the paint into the water.
Field trials of painted test panels at the Sven Lovén Centre for Marine Sciences in Kristineberg are said to have shown that the concept of optimised anti-fouling blends in bottom paints works well.
Marine Paint’s research results for medetomidine have been passed to commercial partner I-Tech AB, and the product is now being marketed under the name Selektope.