Epoxy resin based smart coating of polyurea formaldehyde microcapsules with self-repairing function

A new study focuses on a coating with self-healing polyphenyl formaldehyde microcapsules for corrosion protection of aluminum alloy AA2024.
for research, repairable microcapsules have been evaluated to repair micro-cracks in the coating substrate and effectively inhibit corrosion of the substrate/coating interface during use. The main purpose is to create an innovative pH-based permeable converted polyphenyl formaldehyde (PUF) microcapsule containing 8-hydroxyquinone (8-HQ) as the core material for the production of long-term protection of intelligent epoxy coating aluminum alloy .
self-healing through two mechanisms
the results show that self-healing occurs through two mechanisms: first, the initiating of chain migration of modified coating defects through heat treatment. Secondly, through various polymer-polymer interactions, the soluble hydrogel present in the PUF shell wall is cross-linked. Active corrosion protection is due to the (intelligent) pH response release capability and increased corrosion level of the packaged corrosion inhibitor (8-HQ). At the same time, the inherent rough surface of the manufactured microcapsules is evenly dispersed in the epoxy coating substitut to help improve barrier and adhesion.
the findings have been published in the Journal of Coating Technology and Research Volume 17 (2020).
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