Synergistic Effect of Nanoclay and Barium Sulfate Fillers on the Corrosion Resistance of Polyester Powder Coatings

Authors

Jinbao Huang, Western University
Marshall Shuai Yang, Western UniversityFollow
Chengqian Xian, Western UniversityFollow
James Joseph Noel, Western UniversityFollow
Yolanda S. Hedberg, Western UniversityFollow
Jian Chen, Western UniversityFollow
Ubong Eduok, Western UniversityFollow
Ivan Barker, Western UniversityFollow
Jeffrey Daniel Henderson, Western UniversityFollow
Haiping Zhang, Tianjin UniversityFollow
Liqin Wang, Harbin Institute of TechnologyFollow
Hui Zhang, Western UniversityFollow
Jesse Zhu, Western UniversityFollow

Document Type

Article

Publication Date

Fall 9-25-2023

Journal

Coatings

Volume

13

Issue

10

First Page

1680

URL with Digital Object Identifier

https://doi.org/10.3390/coatings13101680

Notes

Nanoclay has proven to be an active anti-corrosive additive due to the self-repairing effect from nanoclay swelling and expansion, except for its passive barrier effect due to the high aspect ratio. But it is still uncertain how these effects of nanoclay are intertwined with the other components in a complex coating system in corrosive environments. In this study, we examined the combined effects of nanoclays of two particle sizes with a commonly used cost-reducing filler, BaSO₄. By employing neutral salt spray tests, electrochemical analysis, and surface characterization, we identified the optimal conditions for achieving a strong barrier effect. Surprisingly, a relatively low nanoclay dosage of 2% combined with BaSO₄ filler exhibited synergistic behavior. Nanoclay not only compensated for the reduction in the barrier effect owing to the addition of BaSO₄ by offering self-repairing and barrier effects, but also overcame the delamination issues observed at higher nanoclay dosages (4% and above). The coating panel with 2% larger nanoclay and BaSO₄ showed two orders of magnitude higher pore resistance than the coating without nanoclay, remaining at 107 Ω∙cm² after 25 days of immersion. As a result, this coating panel demonstrated significantly slower corrosion expansion and reached a lifetime of 2500 h when creepage exceeded 2 mm in salt spray tests. This study contributes to a full understanding and proper utilization of nanoclay for high-performance, smart anti-corrosive coatings.

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 License.

Citation of this paper:

Huang, J.; Yang, M.S.; Xian, C.; Noël, J.J.; Hedberg, Y.S.; Chen, J.; Eduok, U.; Barker, I.; Henderson, J.D.; Zhang, H.; et al. Synergistic Effect of Nanoclay and Barium Sulfate Fillers on the Corrosion Resistance of Polyester Powder Coatings. Coatings 2023, 13, 1680. https://doi.org/10.3390/coatings13101680