Block Poly(carbonate-ester) Ionomers as High-Performance and Recyclable Thermoplastic Elastomers

Area of Science:

• Polymer Chemistry
• Materials Science
• Sustainable Materials

Background:

• Thermoplastic elastomers from polyesters/carbonates promise enhanced recyclability, degradability, and renewable resource utilization.
• A common challenge is the trade-off between strength and extensibility, limiting their performance.
• Existing materials often fail to meet demanding application requirements due to these limitations.

Purpose of the Study:

• To develop well-defined, reprocessable poly(ester-b-carbonate-b-ester) elastomers.
• To achieve superior mechanical properties including high tensile strength, elasticity, and recovery.
• To ensure full degradability and enable chemical recycling through ester/carbonate linkages.

Main Methods:

• One-pot synthesis combining controlled cyclic monomer ring-opening polymerization and alternating epoxide/anhydride ring-opening copolymerization.
• Incorporation of precisely placed Zinc(II)-carboxylates via dynamic crosslinking of hard domains.
• Conversion to ionomers by reacting vinyl-epoxides to install the Zinc(II)-carboxylates.

Main Results:

• Achieved impressive tensile strengths of 60 MPa, elasticity exceeding 800%, and recovery of 95%.
• Demonstrated fully reversible strain-induced crystallization in the elastomer's soft segments.
• Successfully created dynamically crosslinked hard domains using Zinc(II)-carboxylates.

Conclusions:

• The developed poly(ester-b-carbonate-b-ester) elastomers exhibit exceptional mechanical performance and recyclability.
• The combination of entangled soft segments, reversible crystallization, and dynamic crosslinking is key to superior properties.
• These materials represent a significant advancement in sustainable elastomers, addressing key performance and end-of-life challenges.