Dual-network synergistic lignin-based polyurethane elastomers with high strength, toughness, and broad-temperature-range damping

Existing polyurethane materials struggle to integrate high strength-toughness with superior damping performance, constrained by inherent contradictions in molecular structure design. To overcome this, we report a supramolecular dual-network strategy, constructing a synergistic system of hierarchical hydrogen bonds and chemical cross-links. This architecture enhances lignin-matrix compatibility, suppresses polycaprolactone crystallization, and promotes refined phase separation with dual-scale hard segments. As a result, the designed elastomer achieves a tensile strength of 44.36 MPa alongside an elongation at break of 1551.74%, together with an ultrawide effective damping temperature range of 148 °C (−19 to 129 °C, tan δ ≥ 0.3). The optimal formulation (ULPUEs-2) demonstrates that this dual-network strategy successfully resolves the strength-toughness-damping trade-off. The underlying mechanisms for simultaneous reinforcement-toughening and energy dissipation are systematically elucidated. Moreover, the material integrates additional functionalities including puncture resistance, UV shielding, controlled degradability, and self-healing capability. This multifunctional ensemble aligns the design with the “dual‑carbon” (carbon peak and neutrality) strategy and underpins its potential for versatile applications.