High Bio-Content Thermoplastic Polyurethanes from Azelaic Acid.

Area of Science:

• Polymer Science
• Materials Science
• Sustainable Chemistry

Background:

• Commercialization of sustainable materials requires novel polymers with well-defined properties and end-of-life considerations.
• Limited adoption of renewable monomer-based polyester polyols in thermoplastic polyurethane (TPU) applications necessitates further research into their structure-property relationships.

Purpose of the Study:

• To synthesize and characterize bio-based crystalline and amorphous polyester polyols using azelaic acid and various diols.
• To evaluate the thermal and mechanical properties of thermoplastic polyurethanes (TPUs) derived from these bio-based polyols.
• To assess the potential for commercial viability of these sustainable TPUs.

Main Methods:

• Synthesis of bio-based polyester polyols from azelaic acid and branched/non-branched diols.
• Characterization of polyol viscosity at 70 °C.
• Fabrication and testing of thermoplastic polyurethanes (TPUs) for thermal and mechanical properties.
• Demonstration of prototype products using developed TPUs.

Main Results:

• Polyester polyols exhibited viscosities between 504-781 cP at 70 °C.
• Resulting TPUs demonstrated excellent thermal and mechanical performance.
• TPUs derived from crystalline azelate polyester polyols showed superior mechanical properties compared to those from amorphous polyols.
• Developed TPUs achieved up to 85% bio-carbon content.
• Prototype products including watch bands and cup-shaped forms were successfully demonstrated.

Conclusions:

• Bio-based crystalline polyester polyols are promising for high-performance thermoplastic polyurethanes (TPUs).
• The developed TPUs possess excellent mechanical properties and significant bio-carbon content, supporting sustainable material commercialization.
• Further research on these renewable materials is crucial for developing commercially viable, sustainable products.