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Eric N. Brown

Ph.D. recipient 10/2003, University of Illinois at Urbana-Champaign

Fracture and Fatigue of a Self-Healing Polymer Composite

Polymers are susceptible to damage in the form of cracks, which form deep within the structure where detection is difficult and repair is often impossible. For applications ranging from structural composites to microelectronics, once cracks have formed within polymeric materials, the integrity of the structure is significantly compromised. Here a novel approach is explored for improving the life of thermosetting polymers through the addition of self-healing functionality. The material under investigation is an epoxy matrix composite, which utilizes embedded microcapsules to store a healing agent and an embedded catalyst. A propagating crack exposes particles of catalyst and ruptures the microcapsules, which release healing agent into the crack plane. Polymerization of the healing agent is triggered by contact with the catalyst and bonds the crack faces closed.