Biodegradable optically transparent terpinen-4-ol thin films for marine antifouling applications

Sustainable marine antifouling strategies aim to minimize long term environmental impacts while effectively preventing surface colonization. In this study, we report upon a biodegradable antifouling coating for marine applications. In two stages, thin bilayers were produced using plasma-enhanced chemical vapor deposition of terpinen-4-ol, at applied powers of 100 W initially and then 10 or 25 W. The resulting coatings were characterized for solubility, surface energy, surface roughness and optical transmission. Both coatings exhibited similar solubility over the initial 14 days of observation, though structures deposited at 25 W were significantly more stable after 14 days. Coatings were smoother than the control surface upon which they were deposited and had higher hydrophobicity with transmission efficiencies > 90% (400-1000 run). Field assessments of the samples were carried out in Curralea Lake (Townsville, Australia) to assess their real world performance. Results indicate that the environmentally friendly coatings, terpinen-4-ol plasma polymer influenced antifouling. The proposed mechanism for this effect is the dissolution of the coating coupled with possible antimicrobial properties of the terpinen-4-ol. These results point to the potential usefulness of developing multilayer coatings for extended deployments