Soft-Segment-Tuned Dynamic Polyurethanes With Low Compression Set and Recyclability

Area of Science:

• Materials Science
• Polymer Chemistry

Background:

• High-performance polyurethane (PU) elastomers face a challenge balancing mechanical strength with recyclability.
• Existing materials often compromise one property for the other.

Purpose of the Study:

• To develop recyclable PU elastomers with high mechanical performance.
• To investigate the structure-property relationships in PU elastomers with tailored soft segment ratios.
• To create advanced materials for demanding sealing applications.

Main Methods:

• Synthesized Diels-Alder (DA) dynamic covalently cross-linked PU elastomers (DAPU-EEs).
• Precisely controlled polyether-to-polyester soft segment ratios.
• Evaluated mechanical properties, thermal stability, and recyclability through hot-pressing cycles.

Main Results:

• Optimized DAPU-EEs (DAPU-EE2) demonstrated excellent recyclability, retaining properties after multiple cycles.
• Achieved a low compression set of 15%, outperforming commercial TPU sealing materials.
• Exhibited superior solvent resistance and efficient processability with reduced viscosity.

Conclusions:

• The developed DAPU-EEs offer a practical strategy for balancing mechanical performance and sustainable reprocessing.
• These materials show significant potential for advanced sealing applications requiring durability and recyclability.