Self-healing polymers are a class of smart materials that have the capability of autonomically repairing themselves after damage, without the need for detection or repair by manual intervention. Building on recent breakthrough technology in the design of microencapsulation-based self-healing systems, we are developing self-healing coating systems for extended corrosion protection of steel substrates (Figure 1). A self-healing coating based on this technology would not only extend the lifetime of the corrosion protection system, but would also reduce the cost of labor associated with corrective and preventative maintenance.
The self-healing polymer system described by White et al. in 20011 was based on the Grubbs’ catalyst-initiated ring opening metathesis polymerization (ROMP) of dicyclo-pentadiene (DCPD) in the site of damage, thus healing the damage and restoring structural continuity. While a successful demonstration of microcapsule-based self-healing technology, this approach was not deemed viable for commercial applications due to the chemical stability and cost of the catalyst. Several new chemistries have since been developed for applications in elastomers,2 coatings3 and composites.4 In this paper, we evaluate the application of polydimethylsiloxane (PDMS)-based chemistries in the development of self-healing coatings for heavy-duty industrial and marine applications.