Toughening CO₂‐Derived Copolymer Elastomers Through Ionomer Networking

摘要

Abstract Utilizing carbon dioxide (CO 2 ) to make polycarbonates through the ring‐opening copolymerization (ROCOP) of CO 2 and epoxides valorizes and recycles CO 2 and reduces pollution in polymer manufacturing. Recent developments in catalysis provide access to polycarbonates with well‐defined structures and allow for copolymerization with biomass‐derived monomers; however, the resulting material properties are underinvestigated. Here, new types of CO 2 ‐derived thermoplastic elastomers (TPEs) are described together with a generally applicable method to augment tensile mechanical strength and Young's modulus without requiring material re‐design. These TPEs combine high glass transition temperature ( T g ) amorphous blocks comprising CO 2 ‐derived poly(carbonates) (A‐block), with low T g poly( ε ‐decalactone), from castor oil, (B‐block) in ABA structures. The poly(carbonate) blocks are selectively functionalized with metal‐carboxylates where the metals are Na(I), Mg(II), Ca(II), Zn(II) and Al(III). The colorless polymers, featuring <1 wt% metal, show tunable thermal ( T g ), and mechanical (elongation at break, elasticity, creep‐resistance) properties. The best elastomers show >50‐fold higher Young's modulus and 21‐times greater tensile strength, without compromise to elastic recovery, compared with the starting block polymers. They have wide operating temperatures (−20 to 200 °C), high creep‐resistance and yet remain recyclable. In the future, these materials may substitute high‐volume petrochemical elastomers and be utilized in high‐growth fields like medicine, robotics, and electronics.