Self-Healing Polymer Coatings

Autonomic healing materials respond without external intervention to environmental stimuli in a non-linear and productive fashion and have great potential for advanced engineering systems.  Self-healing coatings which autonomically repair and prevent corrosion of the underlying substrate are of particular interest.  It should be noted that the worldwide cost of corrosion has been estimated to be nearly $300 billion per year.  Recent studies on self-healing polymers have demonstrated repair of bulk mechanical damage.  Various approaches for achieving healing functionality have been demonstrated including encapsulation, reversible chemistry, microvascular networks, nanoparticle phase separation, polyionomers, hollow fibres, and monomer phase separation.  These systems however have serious chemical limitations preventing their use as coatings.  Here we describe a generalized approach, based on the dispersion of microencapsulated healing agent and microencapsulated catalyst within a coating, to create self-healing polymer coating systems and demonstrate the effectiveness of this approach for both model and industrially important coating systems.