A Self-sealing Fiber-reinforced Composite

Abstract

We describe a self-sealing plain weave E-glass epoxy composite with the healing components, microencapsulated dicyclopentadiene (DCPD), and paraffin wax coated Grubbs’ catalyst dispersed throughout the matrix. In this work, sealing is assessed through use of a pressure cell apparatus to detect nitrogen flow through the thickness direction of a damaged composite. A controlled amount of microcracking is introduced through cyclic indentation of opposing surfaces of the sample. The resulting damage zone is proportional to the indentation load. We investigate the effect of DCPD microcapsule size and concentration on the self-sealing ability of plain weave E-glass epoxy composites. For 51 µm diameter capsules (6.5 wt%), 67% of the self-sealing composite panels fully seal with no leaking, compared to 0% of the control panels with no sealing ability. When the amount of damage is reduced, 100% of the self-sealing samples resealed. Sealing performance decreases with smaller diameter capsules (18 µm diameter) and lower capsule concentrations (2.7 wt%), indicating that there is a minimum capsule size and concentration to deliver enough healing agent to seal a given damage volume.