The development of viscoelastic polymers combining excellent mechanical properties and efficient energy dissipation in impact protection is a significant challenge to be faced. Here, we developed an elastomeric polyurethane (PU-PBA/TAx) featuring dual dynamic cross-linking networks (both covalent and noncovalent) by incorporating tannic acid (TA) into a benzeneboronic acid-functionalized polyurethane chain (PU-PBA). PU-PBA/TAx-based materials exhibited excellent mechanical properties and energy dissipation capabilities. The tensile strength and toughness of PU-PBA/TA10 reached, respectively, 44.6 MPa and 332.6 MJ/m3, which are 68 and 12 times higher than those of neat PU-PBA, respectively. Additionally, the numerous H-bond interactions, as well as the reversible dissociation and exchange of borate ester bonds, provided the PU-PBA/TA with multiple energy dissipation pathways, resulting in a maximum energy dissipation ratio of 84.7%. Meanwhile, PU-PBA/TAx exhibited excellent compressive strength under high-speed impact loads (12,500 s–1), with a maximum strength of 253.6 MPa and a toughness of 122.6 MJ m–3. Furthermore, the mechanical strength retention rate of stress-fractured PU-PBA/TA10 elastomer reached 92.0% after three cycles of hot repressing without sacrificing the energy dissipation capacity, demonstrating excellent reprocessing performance. This study may provide a new idea for the preparation and application of next-generation impact-resistant protection materials.
Tannic Acid-Regulated Hierarchically Dynamic Networks with Superior Impact Resistance and Reprocessability
Yang, Weijun;Puglia, Debora;
2026
Abstract
The development of viscoelastic polymers combining excellent mechanical properties and efficient energy dissipation in impact protection is a significant challenge to be faced. Here, we developed an elastomeric polyurethane (PU-PBA/TAx) featuring dual dynamic cross-linking networks (both covalent and noncovalent) by incorporating tannic acid (TA) into a benzeneboronic acid-functionalized polyurethane chain (PU-PBA). PU-PBA/TAx-based materials exhibited excellent mechanical properties and energy dissipation capabilities. The tensile strength and toughness of PU-PBA/TA10 reached, respectively, 44.6 MPa and 332.6 MJ/m3, which are 68 and 12 times higher than those of neat PU-PBA, respectively. Additionally, the numerous H-bond interactions, as well as the reversible dissociation and exchange of borate ester bonds, provided the PU-PBA/TA with multiple energy dissipation pathways, resulting in a maximum energy dissipation ratio of 84.7%. Meanwhile, PU-PBA/TAx exhibited excellent compressive strength under high-speed impact loads (12,500 s–1), with a maximum strength of 253.6 MPa and a toughness of 122.6 MJ m–3. Furthermore, the mechanical strength retention rate of stress-fractured PU-PBA/TA10 elastomer reached 92.0% after three cycles of hot repressing without sacrificing the energy dissipation capacity, demonstrating excellent reprocessing performance. This study may provide a new idea for the preparation and application of next-generation impact-resistant protection materials.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
