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Since the use of organotin antifouling paints was prohibited in 2003, researchers have endeavored to develop novel environment-friendly marine antifouling coatings. We report in successful fabrication model of silicone foul-release (FR) coatings with elastomeric polydimethylsiloxane (PDMS)/spherical silver (Ag) nanocomposites. This modeling design shows evidence to integrate two inhibition modes of (1) chemical inertness and (2) physical repelling force of microfouling. The antifouling nanocomposite models were successfully synthesized via the solution casting technique. In this approach, a series of filler concentrations of Ag nanoparticles (NPs) with particle size << 10 nm and spherical morphology facet dominantly controlled on the {111} lattice plane was used to controlled antifouling models. Surface hydrophobicity, roughness, and free energy properties of the nanocomposites were systematically studied as fouling non-stick factors. Physicomechanical properties were also assessed. Selected bacterial strains were used as microfoulants for laboratory assay investigation for 30 days. Our finding provides important insights into how subtle structural changes in polymer nanocomposites can considerably improve biological activity and simplify surface cleaning. Hydrophobicity, surface inertness, fouling resistance, and surface easy-cleaning properties significantly improved in the nanocomposite design models fabricated with nanofiller loadings of up to 0.1% spherical Ag NPs without changes in the bulk mechanical properties. The fabricated models were subjected to a rigorous test in a field trial in the Red Sea waters. Results show the potential of our models based Ag nanofillers up to 0.1% to approve ecologically friendly antifouling coatings as an alternative to traditional systems. The Ag/PDMS composite models have a long-term durability and antifouling performance, which are important factors in developing effective, stable, and eco-friendly nanocomposites.

The effects of Ag@SiO 2 core-shell nanofiller dispersion and micro-nano binary structure on the selfcleaning and fouling release (FR) in the modelled silicone nano-paints were studied. An ultrahydrophobic polydimethylsiloxane/Ag@SiO 2 core-shell nanocomposite was prepared as an antifouling coating material. Ag@SiO 2 core-shell nanospheres with 60 nm average size and a preferential {111} growth direction were prepared via a facile solvothermal and a modified Stöber methods with a controlled shell thickness. Ag@SiO 2 core-shell nanofillers were inserted in the silicone composite surface via solution casting technique. A simple hydrosilation curing mechanism was used to cure the surface coating.Different concentrations of nanofillers were incorporated in the PDMS matrix for studying the structureproperty relationship. Water contact angle (WCA) and surface free energy determinations as well as atomic force microscopy and scanning electron microscope were used to investigate the surface selfcleaning properties of the nanocomposites. Mechanical and physical properties were assessed as durability parameters. A comparable study was carried out between silicone/spherical Ag@SiO 2 coreshell nanocomposites and other commercial FR coatings. Selected micro-foulants were used for biological and antifouling assessments up to 28 days. Well-distributed Ag@SiO 2 core-shell (0.5 wt%) exhibited the preferable self-cleaning with WCA of 156 and surface free energy of 11.15 mN m À1.