Hydrogenative depolymerization of nylons
MetadataShow full item record
The widespread crisis of plastic pollution demands discovery of new and sustainable approaches to degrade robust plastics such as nylons. Using a green and sustainable approach based on hydrogenation, in the presence of a ruthenium pincer catalyst at 150 oC and 70 bar H2, we report here the first example of hydrogenative depolymerization of conventional, widely used nylons, and polyamides in general. Un-der the same catalytic conditions, we also demonstrate the hydrogenation of a polyurethane to produce diol, diamine and methanol. Additionally, we demonstrate an example where monomers (and oligomers) obtained from the hydrogenation process can be dehydrogenated back to a poly(oligo)amide of approximately similar molecular weight, thus completing a closed loop cycle for recycling of poly-amides. Based on the experimental and DFT studies, we propose a catalytic cycle for the process that is facilitated by metal-ligand cooperativity. Overall, this unprecedented transformation, albeit at the proof of concept level, offers a new approach towards a cleaner route to recycling nylons.
Kumar , A , von Wolff , N , Rauch , M , Zou , Y-Q , Shmul , G , Ben-David , Y , Leitus , G , Avram , L & Milstein , D 2020 , ' Hydrogenative depolymerization of nylons ' , Journal of the American Chemical Society , vol. 142 , no. 33 , pp. 14267-14275 . https://doi.org/10.1021/jacs.0c05675
Journal of the American Chemical Society
Copyright © 2020 American Chemical Society. This is an open access article published under a Creative Commons Attribution (CC-BY) License, which permits unrestricted use, distribution and reproduction in any medium, provided the author and source are cited.
DescriptionThis research was supported by the European Research Council (ERC AdG 692775). D. M. holds the Israel Matz Professorial Chair of Organic Chemistry. A. K. is thankful to the Planning and Budgeting Committee of Israel and Feinberg Graduate School for a (senior) postdoctoral fellowship. Y.-Q. Z. acknowledges the Sustainability and Energy ResearchInitiative (SAERI) foundation for a research fellowship. Computations were performed using HPC resources from GENCI-CINES (Grant 2019 AP010811227).
Items in the St Andrews Research Repository are protected by copyright, with all rights reserved, unless otherwise indicated.