Dynamic bond-enhanced, recyclable polyurethane elastomer with high strength and self-healing properties for advanced 3D printing

Self-healing polyurethanes hold great promise for advanced material applications , yet their practical implementation is often constrained by challenges in processing complex geometries, achieving high self-healing efficiency, and ensuring reusability . In this work, we present a 3D-printable self-healing polyurethane elastomer that combines exceptional mechanical properties with outstanding healing capabilities. The elastomer exhibits an ultimate tensile strength of 3.38 MPa and an elongation at break of 1425.78 %, while achieving a remarkable self-healing efficiency of 95.86 % under thermal treatment at 50 °C for 6 h. This material demonstrates superior durability, with post-healing components capable of towing a vehicle over 5 m, showcasing its robust recovery performance. The enhanced properties arise from the synergistic integration of dynamic disulfide bonds and a soft-hard segment architecture within the polyurethane matrix, enabling efficient healing and mechanical robustness. This study introduces a scalable strategy for fabricating high-performance self-healing elastomers with complex architectures, offering transformative potential for applications in sustainable materials and advanced manufacturing .