Mussel-Inspired Universal Anti-Fogging Coating Based on Maleic Anhydride Copolymers with Customizable Structural Design for Functional Properties

In this study, poly(ethylene-<i>alt</i>-maleic anhydride) (PEMA) was selected as the backbone, and PEMA-<i>g</i>-DA/DMAPA was synthesized through an amidation reaction with dopamine (DA) and <i>N</i>,<i>N</i>-dimethylaminopropylamine (DMAPA). The antifogging performance, stability, universality, and antibacterial property after quaternization of the PEMA-DA-DMAPA coating were tested and analyzed. Experimental results showed that the PEMA-DA-DMAPA coating exhibited great antifogging performance, with the water contact angle (WCA) as low as 10.7°. The coefficient of friction of the PEMA-DA-DMAPA coating decreased significantly compared with that of the substrate. Even after 5 days of immersion or 60 cycling tests, the coating still maintained excellent antifogging properties. This coating can be widely applied to the surfaces of transparent substrates, such as poly(methyl methacrylate)(PMMA), polyethylene terephthalate (PET), and polycarbonate (PC). Specifically, the WCA on the PC surface dropped significantly from 89.5° to 11.9°. After quaternization, the coating exhibited notable antibacterial activity against <i>Staphylococcus aureus</i> (<i>S. aureus</i>), with a maximum antibacterial rate of 97.23%.