Bio-Based, Recyclable and Self-Healing Polyurethane Composites with High Energy Dissipation and Shape Memory

Area of Science:

• Materials Science
• Polymer Chemistry
• Biomaterials

Background:

• Rubber composites are crucial for vibration and noise reduction due to viscoelasticity.
• Petrochemical resource scarcity and performance limitations necessitate bio-based alternatives.
• Self-healing capabilities are desirable for extending product lifespan and safety.

Purpose of the Study:

• To synthesize and characterize a novel bio-based polylactic acid thermoplastic polyurethane (PLA-TPU) composite.
• To evaluate the damping properties, self-healing efficiency, and recyclability of the developed composite.
• To explore potential applications, particularly in areas requiring human-body temperature responsiveness.

Main Methods:

• Synthesis of bio-based PLA-TPU and its composite (PLA-TPU/AO-80).
• Analysis of viscoelastic properties, focusing on the loss factor (tan δ).
• Assessment of self-healing recovery and mechanical property retention after recycling.

Main Results:

• The PLA-TPU/AO-80 composite exhibited a significant increase in the peak loss factor (tan δmax) from 0.87 to 2.12.
• High energy dissipation efficiency of 99% at 50% strain was achieved.
• The healed sample recovered 81.98% of its comprehensive mechanical properties after 15 minutes of heating.
• Tensile strength remained at 93.4% after five recycling cycles.
• The material displayed shape memory properties with a response temperature near human body temperature.

Conclusions:

• The developed bio-based PLA-TPU/AO-80 composite offers superior damping and self-healing capabilities.
• Reversible hydrogen bonds are key to the enhanced viscoelastic and self-healing performance.
• The material's durability, recyclability, and shape memory properties make it suitable for advanced applications, including medical uses.