Flame sprayed environmentally friendly coatings for marine antifouling applications

Marine biofouling has emerged as worldwide serious problems for artificial marine infrastructures. Among the measures taken so far to solve the abovementioned problems, construction of an antifouling layer has been proven to be effective in offering long-term antifouling performances. Antifouling based on the use of biocides is the most important method in modern maritime industries. While TBT-based self-polishing coatings are being replaced by other biocide-releasing coatings, the environmental toxicity of these compounds is also under scrutiny. Therefore, there is a significant interest in developing non-toxic technologies. Green biocides can also be extracted from many types of organisms including terrestrial plants, sea creatures and bacteria. In this study, flame sprayed polyethylene (PE)-garlic composite coatings were developed for marine antifouling applications. Garlic powder were fixed by polymer-based substrate and distributed evenly. Antifouling test indicated excellent antibacterial properties of composite coatings against adhesion of marine Bacillus sp. bacteria. The salt spraying results confirmed that polyethylene and garlic powder as a protective layer delayed the pitting corrosion of carbon steel substrate. Prohibited formation of biofilm on the surfaces of the thermal sprayed composite coatings gives clear insight into their potential applications as antifouling layers in the marine environment.