Chemically recyclable polyesters from CO₂, H₂, and 1,3-butadiene

Area of Science:

• Polymer Chemistry
• Sustainable Materials
• Carbon Capture and Utilization

Background:

• Developing CO2-based polymers with commercializable properties is crucial for economically viable, long-term CO2 fixation.
• Previous efforts have faced challenges in polymerizing certain CO2-derived monomers, limiting the scope of CO2 utilization.

Purpose of the Study:

• To report the first successful polymerization methodology for a previously non-polymerizable six-membered lactone (HL) with substituents adjacent to the ester group.
• To synthesize chemically recyclable polyesters (polyHL) from CO2 and inexpensive bulk chemicals with high CO2 content and large molecular weights.

Main Methods:

• Developed a novel polymerization method for disubstituted six-membered lactones (HL).
• Investigated the critical role of rigorous water impurity removal for successful polymerization.
• Characterized the resulting polyHL for CO2 content, molecular weight, and material properties.

Main Results:

• Successfully synthesized chemically recyclable polyHL with a high CO2 content (28 wt%) and large molecular weights (up to 613.8 kg mol-1).
• Fabricated transparent membranes from polyHL exhibiting promising pressure-sensitive adhesive (PSA) properties.
• Achieved complete monomer recovery from polyHL under mild catalytic conditions.

Conclusions:

• Established a new method for synthesizing valuable CO2-based polymers from a previously unreactive monomer.
• Demonstrated the potential for scalable chemical utilization of CO2, offering economic benefits and CO2 emission mitigation.
• This work paves the way for developing new solid CO2-based polymers to significantly increase CO2 utilization scales.