Novel Carbon Nanotubes-Based Coatings for Marine Applications

S.F. Nitodas, A. Stefopoulos, F. Katsaros, Z. Sideratou
Glonatech S.A., GR

Keywords: marine coatings, antifouling, biofouling, carbon nanotubes, hydrophobic materials, mechanical properties

Summary:

Marine biofouling is caused by the adhesion of barnacles, macroalgae and microbial slimes. On ships hulls, biofouling results in an increase in roughness, which in turn leads to an increase in hydrodynamic drag as the vessel moves through water. Enhanced fuel consumption, hull cleaning, paint removal and repainting, and associated environmental compliance measures all contribute to the costs of biofouling. New, effective, and environmentally compatible options are needed to control fouling. The product introduced in this work represents a key enabling technology for manufacturers to maximize profit and gain competitive advantages. Carbon nanotube (CNTs) composite materials from different types of matrices (epoxy and silicone resins) were developed in order to create superhydrophobic surfaces with fouling release properties. Functionalization of CNTs took place for facilitating the incorporation of the nanotubes into the resins aiming concurrently at the attainment of the aforementioned properties. The obtained surfaces were fully characterized in terms of hydrophobicity as determined by contact angle measurements. Higher abrasion resistance and improved mechanical strength were concurrently achieved, with respect to the pure resins. The materials with the most promising results (contact angle>110°) were immersed in static seawaters to visualize any incurred fouling phenomena as a function of time.