Self-healing flexible laminates for resealing of puncture damage

A flexible self-healing system capable of healing puncture damage has been manufactured. Our material consists of three layers: a poly( dimethyl siloxane) ( PDMS) composite, embedded with a self-healing microcapsule system, sandwiched between two layers of poly( urethane) coated nylon. The total structure thickness ranges between 0.84 and 1.5 mm. A protocol is established in which samples are damaged using a hypodermic needle or a razor blade, and a successful heal is defined as the ability to reseal the damage to withstand a pressure differential across the laminate of 103 kPa (similar to 1 atm). Trends in healing success are analyzed as a function of microcapsule size, self-healing layer thickness, and puncture diameter. Healing varied significantly with microcapsule size, with the maximum healing success rate (100% successfully healed) occurring in samples with 220 mu m microcapsules and a puncture diameter of 0.49 mm. For this puncture size, an increase in microcapsule diameter corresponds to a decrease in healing efficiency. However, samples with larger microcapsules ( up to 500 mu m avg.) demonstrate more effective healing for larger puncture diameters, up to 1.61 mm. Additionally, healing increased with composite layer thickness, and decreased with increasing puncture hole size.