Shape-memory polyurethanes for polar wearables with ultrasensitive multi-monitoring

Abstract Integrating environmental stability and multi-monitoring modules into flexible sensor remains a pivotal scientific challenge. This study presents a supramolecular polyurethane (PU) engineered with fluorine-rich segments that form electrostatic crosslinks with positively charged ionic groups at polymer chain terminals and establish fluorine-dipole interactions with blended ionic liquid (IL) to stabilize ion transport pathways. The resulting ionically conductive elastomer combines shape memory capacity, self-healing property, and cryogenic tolerance, retaining robust mechanical strength (~32.31 MPa), toughness (~107.05 MJ m⁻ 3 ) and substantial ionic conductivity even at −40 °C. Notably, it exhibits a high temperature coefficient of resistance (TCR = 8.05% °C⁻ 1 ) at cryogenic temperatures (−40 °C to −30 °C), making it attractive for the development of cryogenic sensing materials. Additionally, the material exhibits high-sensitivity physiological monitoring capabilities with signal fidelity, serving as ionic skins for accurate physiological signal acquisition. Such multifunctional adaptability positions it as an ideal candidate for next-generation flexible electronics requiring reliable performance in extreme environments.