Title: Rapid Self-Healing of a Structural Polymer via Integration of Microvasculature and Optical Fibers

Authors: Zachary J. Phillips, Jason F. Patrick

DOI: 10.33599/nasampe/s.22.0792

Abstract: Vascular self-healing strategies based on auto-release of reactive liquids from hollow conduits hold promise for repairing internal damage and extending lifetimes of structural polymers and fiber-composites. However, difficulties in achieving in situ mixing of two-part agents, polymerization times on the order of hours/days, and propensity for flow blockages from cross-contamination are existing research challenges limiting adoption of this technology.

Here we describe the recent development of a microvascular-based, self-healing structural epoxy using a one-part, photo-reactive chemistry. The new platform employs internal micro-channels for fracture-induced, liquid healing agent transport to the damage zone in combination with embedded polymer optical fibers (POF) for rapid (minute-scale), light-activated repair. We detail challenges overcome to: (i) achieve adequate vascular fluid delivery and (ii) transmit sufficient light through POF during crack propagation in an aerospace-grade epoxy. In situ self-healing of mode-I fracture toughness via embedded POF is on par with manual, ex situ recovery using an external light source. Moreover, the one-part cationic photochemistry formulated for visible light polymerization is 50x faster and achieves higher healing efficiencies than an established two-part, epoxy/amine system. This latest self-healing advancement is well-poised to eliminate routine inspection and manual repair of structural polymers/composites while enhancing in-service safety and reliability.

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Conference: SAMPE 2022

Publication Date: 2022/05/23

SKU: TP22-0000000792

Pages: 8

Price: $16.00