Delivery of Two-Part Self-Healing Chemistry via Microvascular Networks

✍ Scribed by Kathleen S. Toohey; Christopher J. Hansen; Jennifer A. Lewis; Scott R. White; Nancy R. Sottos

• Publisher: John Wiley and Sons
• Year: 2009
• Tongue: English
• Weight: 450 KB
• Volume: 19
• Category: Article
• ISSN: 1616-301X
• DOI: 10.1002/adfm.200801824

✦ Synopsis

Abstract

Multiple healing cycles of a single crack in a brittle polymer coating are achieved by microvascular delivery of a two‐part, epoxy‐based self‐healing chemistry. Epoxy resin and amine‐based curing agents are transported to the crack plane through two sets of independent vascular networks embedded within a ductile polymer substrate beneath the coating. The two reactive components remain isolated and stable in the vascular networks until crack formation occurs in the coating under a mechanical load. Both healing components are wicked by capillary forces into the crack plane, where they react and effectively bond the crack faces closed. Healing efficiencies of over 60% are achieved for up to 16 intermittent healing cycles of a single crack, which represents a significant improvement over systems in which a single monomeric healing agent is delivered.