A Versatile Microporous Design toward Toughened yet Softened Self-Healing Materials

Area of Science:

• Materials Science
• Polymer Science
• Nanotechnology

Background:

• Self-healing materials are crucial for stretchable electronics, requiring both low modulus for adaptivity and high toughness for crack resistance.
• Current toughening methods for soft self-healing materials offer limited improvements in energy dissipation and often compromise softness and healing ability.

Purpose of the Study:

• To develop a novel toughening strategy for self-healing materials that enhances mechanical properties without sacrificing softness or healing efficiency.
• To introduce a new dissipative mechanism for improved material resilience.

Main Methods:

• Fabrication of a synthetic microporous architecture within self-healing materials.
• Characterization of mechanical properties, including fracture toughness, fractocohesive length, and modulus.
• Evaluation of self-healing kinetics and efficiency.

Main Results:

• The microporous structure achieved a 31.6-fold increase in fracture toughness (100.86 kJ m⁻²) and a 20.7-fold increase in fractocohesive length (12.24 mm).
• The material exhibited significantly enhanced softness (0.43 MPa) and near-perfect autonomous self-healing efficiency (≈100%).
• A novel dissipative mode of adaptable crack movement (Γ_A) was identified, spreading energy dissipation throughout the material.

Conclusions:

• The developed microporous architecture provides unprecedented toughness and softness in self-healing materials.
• This robust material, with superior mechanical properties and healing capabilities, is highly suitable for advanced applications like durable kirigami electronics for wearable devices.
• The findings present a significant advancement in the design of resilient and adaptive soft materials.