Layer-by-layer deposition of antifouling coatings on stainless steel via catechol-amine reaction

Stainless steel (SS) has been widely used as a construction material in maritime structures due to its good corrosion resistance. However, bacteria, algae, barnacles and other marine organisms can readily adhere to its surface in the process of biofouling, leading to serious structure failures and economic losses. In this work, layer-by-layer (LBL) deposition of functional polymer coatings on SS surface provides an alternative approach to combating marine fouling. The catechol-containing antifouling copolymer of dopamine methacrylamide and poly(ethylene glycol) methyl ether methacrylate (P(DMA- co -PEGMEMA)), and amino-rich branched poly(ethyleneimine) (PEI) were assembled sequentially on the SS surface via catechol-amine reaction in a LBL manner. The PEI/P(DMA- co -PEGMEMA) multiple bilayer-coated SS surfaces can effectively reduce the adhesion of bacteria and microalgae (microfouling), and settlement of barnacle cyprids (macrofouling), as compared to the pristine SS surface. The antifouling efficiencies of PEI/P(DMA- co -PEGMEMA) bilayer-coated SS surfaces were also significantly higher than that of the P(DMA- co -PEGMEMA) monolayer-coated SS surface.