Multiscale modification on acrylic resin coating for concrete with silicon/fluorine and graphene oxide (GO) nanosheets

Abstract

In this study, acrylic resin coating for concrete was modified at molecular scale and nano scale, respectively. In order to reduce the surface energy and subsequently increase the bacteriostatic and antifouling performance, acrylic resin was modified with silicone and fluorine. Moreover, GO nanosheets was incorporated to improve the mechanical properties and erosion resistance of the coating. For improving the dispersion, GO was modified with Vinyl triethyl silane when adding into the resin. The results showed that after the modification with silicone and fluorine, the water contact angle of acrylic resin increased from 82.0° to 93.7° and the surface energy decreased from 33.8 mJ/m2 to 24.0 mJ/m2. The bacteriostatic ratio of the modified acrylic resin coating was as high as 99.9%. Based on the morphology of the fracture surfaces of the coating, GO with a dosage of 1.5 wt% improved the mechanical properties of the coating and its bonding strength with concrete substrate. Moreover, after modification at multiscale, the acrylic resin coating exhibited better UV resistance and protection effects on concrete. No chloride penetration was found and the chemical composition on the surface of concrete specimens with acrylic resin/GO coating hardly changed although the specimens were immersed in seawater for 90 days and in organic acid for 30 days.