Reversibly Cross-linked Polymers for Self-Healing Joints and Composites

SensorMetrix proposes to develop innovative self-healing polymers for integration into fibrous composites and adhesive joints. These polymers heal damage in the form of cracks (macro- through nanoscale) at the molecular level through a novel reversible covalent bond. Polymer composites are notorious for their tendency to microcrack in the matrix regions due to thermal cycling , fatigue loading and other situations where high stress concentrations exist at the fiber-matrix interface. Likewise stress concentrations at the adherend-adhesive interface in bonded joints can initiate cracking and lead to premature failure of the structure. Repair in these situations is costly and in many cases impossible due to limited access or risk of further degradation of the structure. A polymer with a built-in mechanism to repair cracks by restoring broken bonds is of great interest for numerous composite and adhesive applications to extend the service life and improve the safety of structural materials, electronic assemblies, storage tanks, ect. SensorMetrix will integrate this polymer with continuous fiber reinforcement to create strong, stiff and light composites with the ability to heal microcracks over multiple cycles. These revolutionary properties will likewise be demonstrated in bonded joints.