Development of a supramolecular polymer based self-healing multilayer system for inflatable structures

Self-healing materials have become more and more interesting for the space industry, since they can lead to the creation of space systems and structures able to repair autonomously after accidental damages caused by collision with micrometeoroids and orbital debris during the entire operational life. The implementation of these novel materials results in higher protection and safety for astronauts, and longer missions in the perspective of lunar bases establishment and manned exploration of Mars. The present study aims to experimentally and numerically characterize an intrinsic self-healing supramolecular polymer that is potentially applicable to space suits, habitats and inflatable structures in general. A dedicated test device has been developed to evaluate the sealing performance of the material through flow rate measurements after a puncture event. The experimental part is followed by the study of the material's constitutive relations including hyperelastic and viscoelastic responses. The related model parameters are computed and calibrated through optimization and data matching tools in order to simulate damage and healing events. Results show that the selected supramolecular polymer possesses effective self-healing abilities also under pressurized conditions, demonstrating its applicability to the considered specific fields in the space sector. Furthermore, for what concerns the analyzed puncture experiments and field of solicitation, the developed model can follow the relaxation process related to the self-healing behavior, since it can predict whether the material is effectively able or not to flow and repair.