No abstract

No abstract

For the first time, a superhydrophobic series of silicone/nanorod‐like TiO2–SiO2 core–shell composites was fabricated by solution casting for marine fouling release (FR) coatings. Hydrothermal technique was used to prepare single crystal TiO2 nanorods as a core structure in the diameter regime of 20 nm and preferentially grown in {101} direction. Hybrid nanorod‐like TiO2–SiO2 core–shell nanofillers were synthesized by sol–gel technique with silica shell thickness of 2–5 nm. The structure‐property relationship was investigated by dispersing various nanofiller concentrations in the silicone matrix. Surface non‐wettability properties were investigated using water contact angle (WCA), surface free energy (SFE), and atomic force microscopy. Coating′s photocatalytic degradation of organic pollutants and microorganisms was also investigated. Selected micro‐ and macro‐fouling strains were used for antifouling assessments in laboratory. The fabricated models were subjected to a rigorous field trial in natural seawater for 6 months in a tropical area. Well‐distributed nanorod‐like TiO2–SiO2 core–shell (0.5 wt.%) exhibited the preferable FR self‐cleaning with WCA of 154° and SFE of 10.45 mN/m.

No abstract

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.