Anticorrosion mechanism of ethylene-chlorotrifluoroeethylene coatings reinforced with hydroxylated carbon nanotubes: An experimental and molecular dynamics simulation study

Carbon nanotubes/ethylene-chlorotrifluoroeethylene (CNT/ECTFE) composite coatings were prepared on the surface of carbon steel via electrostatic spraying and low temperature heat treatment. The influence of hy-droxylated carbon nanotubes on the anticorrosive properties of ECTFE coatings during water penetration stage was investigated through characterization tests of the coating micromorphology, phase structure, hydrophilicity/ hydrophobicity, microhardness and electrochemical corrosion performance. Additionally, simulation analysis of the coating internal structure and water molecular infiltration law by molecular dynamics was conducted. The results indicate that the addition of CNT can augment the efficacy of ECTFE coating against water penetration, thereby improving the corrosion protection performance. This is primarily attributed to the ability of CNT to reinforce structural stability by impeding the free movement of ECTFE molecular segments and obstructing water molecules from infiltrating. Meanwhile, the hydroxyl groups on the surface of CNT can capture a large number of water clusters through hydrogen bonding and restrict the infiltration of water molecules by occupying osmotic channels. In addition, CNT can prolong the penetration path of water through the labyrinth effect.