Tough Self-Healing Elastomers Based on the Host-Guest Interaction of Polycyclodextrin

Area of Science:

• Materials Science
• Polymer Chemistry
• Biomimetic Engineering

Background:

• Developing advanced elastomers with combined high strength, stretchability, and self-healing properties remains a significant challenge.
• Animal muscles provide a natural model for materials exhibiting toughness and autonomous repair mechanisms.

Purpose of the Study:

• To engineer a novel elastomer with biomimetic properties, specifically high mechanical strength, exceptional stretchability, and autonomous self-healing capabilities.
• To investigate the role of supramolecular interactions in achieving these desired material characteristics.

Main Methods:

• Fabrication of a double network (DN) elastomer using a polyacrylate matrix cross-linked by hydrogen bonding.
• Incorporation of a second network via host-guest interactions between polycyclodextrin and adamantane (Ad) groups.
• Characterization of mechanical properties (tensile strength, strain) and self-healing efficiency under ambient conditions.

Main Results:

• The developed DN elastomer exhibits a tensile strength of approximately 6.7 MPa and a high strain of about 950%.
• Autonomous self-healing is achieved by simple contact of damaged surfaces at ambient conditions.
• Recovered tensile strength after self-healing exceeds 4.5 MPa, surpassing existing spontaneous self-healing elastomers.

Conclusions:

• The designed double network elastomer successfully mimics the toughness and self-healing capabilities of animal muscles.
• Supramolecular host-guest interactions are crucial for load sharing, energy dissipation, and driving the autonomous self-healing process.
• This biomimetic material offers a promising platform for applications requiring durable, stretchable, and repairable materials.