Carbon dioxide is inexpensive and abundant, and its prevalence as waste makes it attractive as a sustainable chemical feedstock. Although there are examples of copolymerizations of CO2 with high-energy monomers, the direct copolymerization of CO2 with olefins has not been reported. Herein, an alternate route to functionalizable, recyclable polyesters derived from CO2, butadiene and hydrogen via an intermediary lactone, 3-ethyl-6-vinyltetrahydro-2H-pyran-2-one, is described. Catalytic ring-opening polymerization of the lactone by 1,5,7-triazabicyclo[4.4.0]dec-5-ene yields polyesters with molar masses up to 13.6 kg/mol and pendent vinyl sidechains that can undergo post-polymerization functionalization. The polymer has a low ceiling temperature of 138 ºC, allowing for facile chemical recycling, and is inherently biodegradable under aerobic aqueous conditions (OECD-301B protocol). These results mark the first example of a well-defined polyester derived from CO2, olefins and hydrogen, expanding access to new polymer feedstocks that were once considered unfeasible.
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This content will become publicly available on March 13, 2025
Sustainable Copolymer Synthesis from Carbon Dioxide and Butadiene
Carbon dioxide (CO2) has long been recognized as an ideal C1 feedstock comonomer for producing sustainable materials because it is renewable, abundant, and cost-effective. However, activating CO2 presents a significant challenge because it is highly oxidized and stable. A CO2/butadiene-derived δ-valerolactone (EVP), generated via palladium-catalyzed telomerization between CO2 and butadiene, has emerged as an attractive intermediate for producing sustainable copolymers from CO2 and butadiene. Owing to the presence of two active carbon–carbon double bonds and a lactone unit, EVP serves as a versatile intermediate for creating sustainable copolymers with a CO2 content of up to 29 wt % (33 mol %). In this Review, advances in the synthesis of copolymers from CO2 and butadiene with divergent structures through various polymerization protocols have been summarized. Achievements made in homo- and copolymerization of EVP or its derivatives are comprehensively reviewed, while the postmodification of the obtained copolymers to access new polymers are also discussed. Meanwhile, potential applications of the obtained copolymers are also discussed. The literature references were sorted into sections based on polymerization strategies and mechanisms, facilitating readers in gaining a comprehensive view of the present chemistry landscape and inspiring innovative approaches to synthesizing novel CO2-derived copolymers.
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- Award ID(s):
- 1901635
- NSF-PAR ID:
- 10498406
- Publisher / Repository:
- ACS Publications
- Date Published:
- Journal Name:
- Chemical Reviews
- Volume:
- 124
- Issue:
- 6
- ISSN:
- 0009-2665
- Page Range / eLocation ID:
- 3590 to 3607
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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