The alternating copolymerization of epoxides and cyclic anhydrides is an increasingly popular route to aliphatic polyesters that are of interest as biodegradable replacements for petroleum-based polymers and for use in the biomedical field. However, broad and bimodal molecular weight distributions in these polymerizations continues to be an issue, limiting synthesis of multiblock copolymers. By use of a bifunctional catalytic system, the reversible-deactivation anionic alternating ring-opening copolymerization of epoxides and cyclic anhydrides gives unimodal polymers with values generally less than 1.07. This allowed for the formation of well-defined triblock copolymers. Additionally, by incorporating both aldehyde and alkene functionalities into the polymer, orthogonal post-polymerization modification was achieved, giving access to well-defined highly modifiable aliphatic polyesters.
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http://dx.doi.org/10.1039/c7sc03643d | DOI Listing |
J Am Chem Soc
January 2025
Polymer Synthesis Laboratory, Laboratory, Chemistry Program, KAUST Catalysis Center, Physical Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955, Saudi Arabia.
J Am Chem Soc
January 2025
Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853-1301, United States.
Direct incorporation of malonate units into polymer backbones is a synthetic challenge. Herein, we report the alternating and controlled anionic copolymerization of epoxides and Meldrum's acid (MA) derivatives to access poly(alkyl malonates) using (-bis(salicylidene)phenylenediamine)AlCl and a tris(dialkylamino)cyclopropenium chloride cocatalyst. This unique copolymerization yields a malonate-containing repeat unit while releasing a small molecule upon MA-derivative ring-opening.
View Article and Find Full Text PDFChem Commun (Camb)
December 2024
Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University, Tsushima, Okayama 700-8530, Japan.
Inorg Chem
December 2024
Department Chemistry, University of Oxford, Chemistry Research Laboratory, 12 Mansfield Road, Oxford, OX1 3TA U.K.
The ring-opening copolymerization (ROCOP) of epoxides with CO or anhydrides is a promising strategy to produce sustainable polycarbonates and polyesters. Currently, most catalysts are reliant on scarce and expensive cobalt as the active center, while more abundant aluminum and iron catalysts often suffer from lower activities. Here, two novel heterodinuclear catalysts, featuring abundant Al(III), Fe(III), and K(I) active centers, are synthesized, and their performance in the polymerization of four different monomer combinations is compared to that of their Co(III) analogue.
View Article and Find Full Text PDFInt J Biol Macromol
December 2024
Key Laboratory of Bio-based Material Science and Technology (Ministry of Education), Northeast Forestry University, Harbin 150040, China; Key Laboratory of Lignocellulosic Material Science and Technology of Heilongjiang Province, Harbin 150040, China. Electronic address:
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