Chapter 13 - Antifouling mechanisms in and beyond nature: leverages in realization of bioinspired biomimetic antifouling coatings

Abstract

Superhydrophic coatings (∼150–170 degrees) are the only viable way to combat the problem of biofouling in the marine environment. Nontoxic, low–surface energy foul-release coatings of polydimethylsiloxane dominate the market. Their antifouling performance depends on shear forces and the cohesive failure of bioadhesives of fouling organisms. However, the increased adhesion of bacteria and diatoms on hydrophobic polydimethylsiloxane coatings (∼110 degrees) needs to be overcome. Increasing the hydrophobicity of polymers above ∼150 degrees deters their attachment. Several approaches using chemical addition and surface modification have yielded successful results, they result in the loss of nontoxicity in the coating. Physical antifouling mechanisms such as altering the surface nanotopography and microtopography are successful but do not last long and lack methods for replicating natural antifouling topographies. True nontoxic antifouling on PDMS may be achieved only through biomimetic approaches.