Bioinspired super-tough polyurethane elastomers with block modules using sacrificial bonds

Area of Science:

• Polymer Science
• Materials Science
• Biomaterials Engineering

Background:

• Stretchable and self-healing elastomers are crucial for advanced applications like electronic skin and soft robotics.
• Synthesizing elastomers with extreme stretchability, high toughness, and self-recoverability remains a significant challenge.

Purpose of the Study:

• To develop a novel self-healing elastomer by integrating multiple dynamic bonds.
• To achieve enhanced mechanical properties including extreme stretchability, high toughness, and self-recoverability.

Main Methods:

• Incorporation of quadruple hydrogen bonds (UPy) and metal-coordination bonds (DAP-Fe(iii)) into a linear polyurethane network.
• Utilizing synergistic dynamic bonds inspired by biological tissues and mussel byssus.

Main Results:

• The synthesized polyurethane elastomer demonstrated high tensile stress (∼30 MPa) and extreme stretchability (∼4100%).
• Exceptional toughness (∼470 MJ m⁻³) and excellent self-recoverability and self-healing capabilities were achieved.
• The dynamic bonds facilitated energy dissipation, enhancing robustness while maintaining stretchability.

Conclusions:

• A biomimetic strategy using synergistic dynamic bonds offers an effective approach for creating advanced polymers.
• This new elastomer possesses a unique combination of properties suitable for demanding applications.