Formation of Antifouling Brushes on Various Substrates Using a Melanin-Inspired Initiator Film

Abstract

In this study, we developed a substrate-independent initiator film that can undergo surface-initiated polymerization to form an antifouling brush. Inspired by the melanogenesis found in nature, we synthesized a tyrosine-conjugated bromide initiator (Tyr-Br) that contains phenolic amine groups as the dormant coating precursor and α-bromoisobutyryl groups as the initiator. The resultant Tyr-Br was stable under ambient air conditions and underwent melanin-like oxidation only in the presence of tyrosinase to form an initiator film on various substrates. Subsequently, an antifouling polymer brush was formed using air-tolerant activators regenerated by electron transfer for atom transfer radical polymerization (ARGET ATRP) of zwitterionic carboxybetaine. The entire surface coating procedure, including the initiator layer formation and ARGET ATRP, occurred under aqueous conditions and did not require organic solvents or chemical oxidants. Therefore, antifouling polymer brushes can be feasibly formed not only on experimentally preferred substrates (e.g., Au, SiO 2 , and TiO 2 ) but also on polymeric substrates such as poly(ethylene terephthalate) (PET), cyclic olefin copolymer (COC), and nylon.

Formation of Amphiphilic Zwitterionic Thin Poly(SBMA-co-TFEMA) Brushes on Solid Surfaces for Marine Antifouling Applications

“…Therefore, various methods are being investigated to prevent biofouling, among which the use of antifouling polymer coatings has received considerable attention owing to its environmental friendliness. − Polymers with good hydrophilicity are widely utilized as antifouling coatings because the hydration layer formed on hydrophilic polymer coatings in water serves as a physical barrier to prevent the adherence of marine organisms to the substrate surface . Zwitterionic polymers prepared from monomers such as sulfobetaine (SB), phosphorylcholine, and carboxybetaine (CB) are typical hydrophilic polymers with antifouling properties. − These polymers have been successfully applied in surface coating technologies to achieve excellent marine antifouling properties. However, zwitterionic polymer coatings tend to adsorb sediments when exposed to the marine environment. , This results in a reduction in the antifouling performance of the coating, necessitating the development of alternative coating materials.…”