Robust icephobic epoxy coating using maleic anhydride as a crosslinking agent
In severely cold regions, it is very difficult to prevent the formation of ice on solid surfaces, even on superhydrophobic (SH) surfaces. Compared with anti-icing surfaces, icephobic surfaces are more useful in practice.
In a new work, a traditional epoxy coating was modified by using maleic anhydride (MAH) as a crosslinking agent, in addition to filling a small amount of epoxy resin grafted with fluorine containing chains (FEP). The wettability and the mechanical properties of the modified coating, as well as the adhesive strength of ice on the coating surface and the stability of the icephobic properties of the coating, were systematically studied.
The results showed that the modified coating surface became more hydrophobic and the force required to remove ice from the surface was less than that needed for removing on the unmodified coating surface. Furthermore, the modified coating has excellent mechanical properties.
Hydrophobicity even after sanding with sandpaper
After sanding with abrasive paper, the unmodified coating surface is more hydrophilic, whereas the modified coating surface retains its hydrophobicity. X-ray photoelectron spectroscopy (XPS) indicates that compared with crosslinking by traditional polyamides, crosslinking using MAH greatly reduces the number of polar groups on the coating surface. The FEP introduction further reduces the free energy of the coating surface. As a result, the modified epoxy coating exhibits excellent icephobic performance.
The study is regarded to be helpful for the design of icephobic epoxy coatings for use in practical applications. For example, it may make the de-icing on the underside of trains running in cold regions become more easily.
The study has been published in Progress in Organic Coatings, Volume 142, May 2020.
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