Eco-friendly bio-based epoxy coatings for corrosion-resistant and self-cleaning applications

摘要

Corrosion and contamination of engineering metals and alloys can cause serious problems to the functionality and aesthetic appearance of pipelines, bridges, highways, vehicles, and even home a ppliances, leading to public safety hazards and economic loss. Epoxy resin has been widely applied as a protective coating due to its excellent properties. However, the raw material for industrially available epoxy, bisphenol A (BPA), is derived from fossil resources. BPA is proven to be harmful to the human endocrine system. Therefore, a sustainable and bio -based green epoxy resin would be ideal to replace the fossil -derived epoxy. In this work, an eco -friendly bio-epoxy coating without volatile organic so lvents was fabricated by introducing nanoparticles, (3 -glycidyloxypropyl) trimethoxysilane (GLYMO) into the isosorbide - based epoxy resin and hydroxyl -terminated polydimethylsiloxane (PDMS). A superhydrophobic bio-epoxy coating was achieved with a contact angle of around 153° by optimizing the coating formulation. Meanwhile, a slippery liquid -infused porous surface (SLIP) coating was obtained by infusing silicone fluid to the optimal superhydrophobic bio-epoxy coating, exhibiting an extremely low sliding ang le below 1° . Both the superhydrophobic and SLIP coatings exhibited good water repellency and corrosion resistance. Electrochemical measurement results showed that the two produced coatings have a decrease of 1-2 orders of magnitude in the corrosion current density and a positive shift from −0.306 V to −0.265 V and −0.282 V in the corrosion potential as compared to the bare substrate. Furthermore, the SLIP coating was enhanced to display better self-cleaning performance and proven to function well after the weathering resistance test.