Investigating the Effects of Graphene Content and Application Method on Surface Properties of Vinyl Ester/Silica Aerogel Coatings

Vinyl ester (VE) based nanocomposite coatings, loaded with an optimum content of silica aerogels, were fabricated on aluminum. Different graphene contents (1, 2, and 3% w/w) were applied via one-step and two-step spraying methods. Surface properties exhibited pronounced changes for the two-step coatings but remained nearly unchanged for the one-step coatings. Graphene was localized in the bulk of one-step coatings whereas the two-step method led to the aggregation of graphene nanoplatelets on the coating surface. Depending on the graphene content, small stacks (2 mu m) to large agglomerations (20 mu m) were detected on the surface of two-step coatings. The water contact angle was essentially increased from 61 degrees for the pure VE coating to 96 degrees and 115 degrees upon the incorporation of silica aerogel and induction of an individual graphene layer, respectively. Such enhanced hydrophobicity was the major reason for the improved corrosion protection properties as found by Tafel polarization plots. The maximum protection efficiency was obtained for the two-step coating loaded by 2% graphene (eta=99.5%). In conclusion, vinyl ester resin was found to be a great candidate for applications where high-performance coatings with improved corrosion resistance are needed. Moreover, the use of graphene, as an individual layer on the coating surface, and the utilization of silica aerogel, as a corrosion protective additive, were demonstrated to be a promising approach in real-life corrosion protection applications.

Automated summary

Vinyl ester-based nanocomposite coatings loaded with graphene and silica aerogel demonstrated excellent corrosion resistance and hydrophobicity, making them suitable for high-performance coating applications.