Materials that are capable of puncture healing upon impact show great promise for space exploration applications wherein an internal breach caused by micrometeoroid impacts that would normally be considered catastrophic would now be self-contained. This type of material also provides a cross-cutting route for improved damage tolerance in load bearing structures and a means of self-mitigation or self-reliability in respect to overall vehicle health and aircraft durability. In puncture healing materials, healing is triggered by the ballistic or damage event. (Ballistics tests are used to simulate micro-meteoroid damage). The force of the bullet on material and the material's response to the bullet (viscoelastic properties) activates healing in these materials. In this regard, our current efforts are focused on developing novel lightweight, self-healing systems where self-repair is induced by the forces imparted by the damage event itself. This is possible because damage is induced by an energetic source – high velocity projectile impact. Designing and synthesizing a structural polymer matrix, that has the inherent ability to self-heal within fractions of seconds after impact damage is incurred, greatly improves vehicle safety by increasing the design allowable for strength, resulting in a more efficient structure. The new structural polymer envisioned will be designed such that recovery can occur autonomously or be activated after an application of a specific stimulus (e.g. heat, radiation). Effective self-healing requires that these materials heal quickly following low- to mid-velocity impacts, while retaining structural integrity.
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