Polymer composite systems are often exposed to small-scale damage. If this damage occurs in the form of cracks that are on a small enough scale, it is possible for the composite to undergo autonomous repair or "self-healing". This process of self-healing without input from the outside is meant to mimic the ability of biological materials to repair themselves. Healing in the composites is achieved through the addition of a microencapsulated healing agent and a catalyst to the matrix polymer. Completion of the self-healing process requires a suitable...