Biobased Anti-Adhesive Marine Coatings from Polyhydroxyalkanoates and Polysaccharides

Abstract

Due to environmental regulations, antifouling marine coatings must be gradually replaced by biocide-free coatings. Marine organisms weakly adhere to fouling release coatings, presenting a low surface free energy and a high elasticity, so they can be readily removed by the sheer force of water. Currently, these materials are mainly composed of petrochemical polymers, such as silicone or fluoropolymers, with hydrophilic polymers as additives. However, following the ever-increasing environmental concerns, the research on new, alternative, eco-friendly coatings is oriented towards the use of biobased polymers from renewable resources. Two main families have been studied: polyhydroxyalkanoates (PHAs) and polysaccharides. PHAs are produced by bacteria in stressful conditions, while polysaccharides are extracted from plants, animals, or micro-organisms such as bacteria, in which case they are called exopolysaccharides (EPS). Since the use of these polymers is a non-toxic approach to controlling fouling colonization, this review provides an overview of these biobased polymers for their applications in new anti-adhesive marine coatings.

Antifouling Performance and Sustained Release Behavior of Ethanol Extract from the Root of Stellera chamaejasme

“…When the adhesion experiment was combined with the fluorescence quenching data of Chlorella and Dunaliella tertiolecta, Sc can reduce the activity of algae and prevent biological fouling. This mechanism is different from hydrophilic coating and oleophobic coating which depends on surface wettability [32]. To further investigate the antifouling mechanism of Sc, the fluorescence quenching experiments of Chlorella and Dunaliella tertiolecta were carried out.…”

Biocidal Coatings against Gram-Positive Bacteria from Linear and Branched Polycations: The Decisive Role of the Diffusion Coefficients of Macromolecules

“…Polymer coatings are widely used as protective layers to prevent formation of biofilms on different surfaces [38][39][40]. In general, these protective polymers could be divided in classes of anti-fouling coatings, bacteria-killing coatings and matrixes for distribution of low-molecular-weight biocides.…”

Organic–Inorganic Composite Antifouling Coatings with Complementary Bioactive Effects

“…Therefore, the antifouling effect of surfaces with both functions is more desirable. Non-adhesive surfaces inhibit initial microbial adherence [9], while bactericidal functions help kill adherent bacterial cells [10]. Ji et al [11] prepared polyurethane (PU) coatings with synergistically enhanced antimicrobial mechanisms consisting of low surface free energy and bactericidal agents, which exhibited excellent antimicrobial properties and durability.…”