1
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Yang S, Du S, Zhu J, Ma S. Closed-loop recyclable polymers: from monomer and polymer design to the polymerization-depolymerization cycle. Chem Soc Rev 2024. [PMID: 39177226 DOI: 10.1039/d4cs00663a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/24/2024]
Abstract
The extensive utilization of plastic, as a symbol of modern technological society, has consumed enormous amounts of finite and non-renewable fossil resources and produced huge amounts of plastic wastes in the land or ocean, and thus recycling and reuse of the plastic wastes have great ecological and economic benefits. Closed-loop recyclable polymers with inherent recyclability can be readily depolymerized into monomers with high selectivity and purity and repolymerized into polymers with the same performance. They are deemed to be the next generation of recyclable polymers and have captured great and increasing attention from academia and industry. Herein, we provide an overview of readily closed-loop recyclable polymers based on monomer and polymer design and no-other-reactant-involved reversible ring-opening and addition polymerization reactions. The state-of-the-art of circular polymers is separately summarized and discussed based on different monomers, including lactones, thiolactones, cyclic carbonates, hindered olefins, cycloolefins, thermally labile olefin comonomers, cyclic disulfides, cyclic (dithio) acetals, lactams, Diels-Alder addition monomers, Michael addition monomers, anhydride-secondary amide monomers, and cyclic anhydride-aldehyde monomers, and polymers with activatable end groups. The polymerization and depolymerization mechanisms are clearly disclosed, and the evolution of the monomer structure, the polymerization and depolymerization conditions, the corresponding polymerization yield, molecular weight, performance of the polymers, monomer recovery, and depolymerization equipment are also systematically summarized and discussed. Furthermore, the challenges and future prospects are also highlighted.
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Affiliation(s)
- Shuaiqi Yang
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, Wuxi, 214122, P. R. China.
| | - Shuai Du
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, Wuxi, 214122, P. R. China.
| | - Jin Zhu
- Key Laboratory of Bio-based Polymeric Materials Technology and Application of Zhejiang Province, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, P. R. China
| | - Songqi Ma
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, Wuxi, 214122, P. R. China.
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2
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Lo CY, Koutsoukos KP, Nguyen DM, Wu Y, Angel Trujillo DA, Miller T, Shrestha T, Mackey E, Damani VS, Kanbur U, Opila R, Martin DC, Kaphan D, Kayser LV. Imidazolium-Based Sulfonating Agent to Control the Degree of Sulfonation of Aromatic Polymers and Enable Plastics-to-Electronics Upgrading. JACS AU 2024; 4:2596-2605. [PMID: 39055151 PMCID: PMC11267550 DOI: 10.1021/jacsau.4c00355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/19/2024] [Revised: 06/13/2024] [Accepted: 06/24/2024] [Indexed: 07/27/2024]
Abstract
The accumulation of plastic waste in the environment is a growing environmental, economic, and societal challenge. Plastic upgrading, the conversion of low-value polymers to high-value materials, could address this challenge. Among upgrading strategies, the sulfonation of aromatic polymers is a powerful approach to access high-value materials for a range of applications, such as ion-exchange resins and membranes, electronic materials, and pharmaceuticals. While many sulfonation methods have been reported, achieving high degrees of sulfonation while minimizing side reactions that lead to defects in the polymer chains remains challenging. Additionally, sulfonating agents are most often used in large excess, which prevents precise control over the degree of sulfonation of aromatic polymers and their functionality. Herein, we address these challenges using 1,3-disulfonic acid imidazolium chloride ([Dsim]Cl), a sulfonic acid-based ionic liquid, to sulfonate aromatic polymers and upgrade plastic waste to electronic materials. We show that stoichiometric [Dsim]Cl can effectively sulfonate model polystyrene up to 92% in high yields, with minimal defects and high regioselectivity for the para position. Owing to its high reactivity, the use of substoichiometric [Dsim]Cl uniquely allows for precise control over the degree of sulfonation of polystyrene. This approach is also applicable to a wide range of aromatic polymers, including waste plastic. To prove the utility of our approach, samples of poly(styrene sulfonate) (PSS), obtained from either partially sulfonated polystyrene or expanded polystyrene waste, are used as scaffolds for poly(3,4-ethylenedioxythiophene) (PEDOT) to form the ubiquitous conductive material PEDOT:PSS. PEDOT:PSS from plastic waste is subsequently integrated into organic electrochemical transistors (OECTs) or as a hole transport layer (HTL) in a hybrid solar cell and shows the same performance as commercial PEDOT:PSS. This imidazolium-mediated approach to precisely sulfonating aromatic polymers provides a pathway toward upgrading postconsumer plastic waste to high-value electronic materials.
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Affiliation(s)
- Chun-Yuan Lo
- Department
of Chemistry and Biochemistry, University
of Delaware, Newark, Delaware 19716, United States
| | - Kelsey P. Koutsoukos
- Department
of Materials Science and Engineering, University
of Delaware, Newark, Delaware 19716, United States
| | - Dan My Nguyen
- Department
of Chemistry and Biochemistry, University
of Delaware, Newark, Delaware 19716, United States
| | - Yuhang Wu
- Department
of Materials Science and Engineering, University
of Delaware, Newark, Delaware 19716, United States
| | | | - Tabitha Miller
- Chemical
Sciences and Engineering Division, Argonne
National Laboratories, Lemont, Illinois 60439, United States
| | - Tulaja Shrestha
- Department
of Chemistry and Biochemistry, University
of Delaware, Newark, Delaware 19716, United States
| | - Ethan Mackey
- Department
of Chemistry and Biochemistry, University
of Delaware, Newark, Delaware 19716, United States
| | - Vidhika S. Damani
- Department
of Materials Science and Engineering, University
of Delaware, Newark, Delaware 19716, United States
| | - Uddhav Kanbur
- Chemical
Sciences and Engineering Division, Argonne
National Laboratories, Lemont, Illinois 60439, United States
| | - Robert Opila
- Department
of Materials Science and Engineering, University
of Delaware, Newark, Delaware 19716, United States
| | - David C. Martin
- Department
of Materials Science and Engineering, University
of Delaware, Newark, Delaware 19716, United States
- Department
of Biomedical Engineering, University of
Delaware, Newark, Delaware 19716, United States
| | - David Kaphan
- Chemical
Sciences and Engineering Division, Argonne
National Laboratories, Lemont, Illinois 60439, United States
| | - Laure V. Kayser
- Department
of Chemistry and Biochemistry, University
of Delaware, Newark, Delaware 19716, United States
- Department
of Materials Science and Engineering, University
of Delaware, Newark, Delaware 19716, United States
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3
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Mountaki S, Whitfield R, Liarou E, Truong NP, Anastasaki A. Open-Air Chemical Recycling: Fully Oxygen-Tolerant ATRP Depolymerization. J Am Chem Soc 2024; 146:18848-18854. [PMID: 38958656 PMCID: PMC11258787 DOI: 10.1021/jacs.4c05621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2024] [Revised: 06/17/2024] [Accepted: 06/24/2024] [Indexed: 07/04/2024]
Abstract
While oxygen-tolerant strategies have been overwhelmingly developed for controlled radical polymerizations, the low radical concentrations typically required for high monomer recovery render oxygen-tolerant solution depolymerizations particularly challenging. Here, an open-air atom transfer radical polymerization (ATRP) depolymerization is presented, whereby a small amount of a volatile cosolvent is introduced as a means to thoroughly remove oxygen. Ultrafast depolymerization (i.e., 2 min) could efficiently proceed in an open vessel, allowing a very high monomer retrieval to be achieved (i.e., ∼91% depolymerization efficiency), on par with that of the fully deoxygenated analogue. Oxygen probe studies combined with detailed depolymerization kinetics revealed the importance of the low-boiling point cosolvent in removing oxygen prior to the reaction, thus facilitating effective open-air depolymerization. The versatility of the methodology was demonstrated by performing reactions with a range of different ligands and at high polymer loadings (1 M monomer repeat unit concentration) without significantly compromising the yield. This approach provides a fully oxygen-tolerant, facile, and efficient route to chemically recycle ATRP-synthesized polymers, enabling exciting new applications.
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Affiliation(s)
- Stella
Afroditi Mountaki
- Laboratory
of Polymeric Materials, Department of Materials, ETH Zurich, Zurich 8093, Switzerland
| | - Richard Whitfield
- Laboratory
of Polymeric Materials, Department of Materials, ETH Zurich, Zurich 8093, Switzerland
| | - Evelina Liarou
- Department
of Chemistry, University of Warwick Library Road, Coventry CV4 7SH, U.K.
| | - Nghia P. Truong
- Laboratory
of Polymeric Materials, Department of Materials, ETH Zurich, Zurich 8093, Switzerland
| | - Athina Anastasaki
- Laboratory
of Polymeric Materials, Department of Materials, ETH Zurich, Zurich 8093, Switzerland
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4
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De Alwis Watuthanthrige N, Whitfield R, Harrisson S, Truong NP, Anastasaki A. Thermal Solution Depolymerization of RAFT Telechelic Polymers. ACS Macro Lett 2024; 13:806-811. [PMID: 38857492 PMCID: PMC11256755 DOI: 10.1021/acsmacrolett.4c00286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2024] [Revised: 06/03/2024] [Accepted: 06/04/2024] [Indexed: 06/12/2024]
Abstract
Thermal solution depolymerization is a promising low-temperature chemical recycling strategy enabling high monomer recovery from polymers made by controlled radical polymerization. However, current methodologies predominantly focus on the depolymerization of monofunctional polymers, limiting the material scope and depolymerization pathways. Herein, we report the depolymerization of telechelic polymers synthesized by RAFT polymerization. Notably, we observed a significant decrease in the molecular weight (Mn) of the polymers during monomer recovery, which contrasts the minimal Mn shift observed during the depolymerization of monofunctional polymers. Introducing Z groups at the center or both ends of the polymer resulted in distinct kinetic profiles, indicating partial depolymerization of the bifunctional polymers, as supported by mathematical modeling. Remarkably, telechelic polymers featuring R-terminal groups showed up to 68% improvement in overall depolymerization conversion compared to their monofunctional analogues, highlighting the potential of these materials in chemical recycling and the circular economy.
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Affiliation(s)
| | - Richard Whitfield
- Laboratory
of Polymeric Materials, Department of Materials, ETH Zurich, Zurich, 8093, Switzerland
| | - Simon Harrisson
- Laboratoire
de Chimie des Polymères Organiques, University of Bordeaux/Bordeaux-INP/CNRS UMR5629, Pessac 33607, France
| | - Nghia P. Truong
- Laboratory
of Polymeric Materials, Department of Materials, ETH Zurich, Zurich, 8093, Switzerland
| | - Athina Anastasaki
- Laboratory
of Polymeric Materials, Department of Materials, ETH Zurich, Zurich, 8093, Switzerland
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5
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Parkatzidis K, Wang HS, Anastasaki A. Photocatalytic Upcycling and Depolymerization of Vinyl Polymers. Angew Chem Int Ed Engl 2024; 63:e202402436. [PMID: 38466624 DOI: 10.1002/anie.202402436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Revised: 03/10/2024] [Accepted: 03/11/2024] [Indexed: 03/13/2024]
Abstract
Photocatalytic upcycling and depolymerization of vinyl polymers have emerged as promising strategies to combat plastic pollution and promote a circular economy. This mini review critically summarizes current developments in the upcycling and degradation of vinyl polymers including polystyrene and poly(meth)acrylates. Of these material classes, polymethacrylates possess the unique possibility to undergo a photocatalytic depolymerization back to monomer under thermodynamically favourable conditions, thus presenting significant advantages over traditional thermal strategies. Our perspective on current formidable challenges and potential future directions are also discussed.
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Affiliation(s)
- Kostas Parkatzidis
- Department of Materials Science, ETH Zurich, Vladimir-Prelog-Weg 5, 8093, Zürich, Switzerland
| | - Hyun Suk Wang
- Department of Materials Science, ETH Zurich, Vladimir-Prelog-Weg 5, 8093, Zürich, Switzerland
| | - Athina Anastasaki
- Department of Materials Science, ETH Zurich, Vladimir-Prelog-Weg 5, 8093, Zürich, Switzerland
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6
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Ko K, Lundberg DJ, Johnson AM, Johnson JA. Mechanism-Guided Discovery of Cleavable Comonomers for Backbone Deconstructable Poly(methyl methacrylate). J Am Chem Soc 2024; 146:9142-9154. [PMID: 38526229 DOI: 10.1021/jacs.3c14554] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/26/2024]
Abstract
The development of cleavable comonomers (CCs) with suitable copolymerization reactivity paves the way for the introduction of backbone deconstructability into polymers. Recent advancements in thionolactone-based CCs, exemplified by dibenzo[c,e]-oxepine-5(7H)-thione (DOT), have opened promising avenues for the selective deconstruction of multiple classes of vinyl polymers, including polyacrylates, polyacrylamides, and polystyrenics. To date, however, no thionolactone CC has been shown to copolymerize with methacrylates to an appreciable extent to enable polymer deconstruction. Here, we overcome this challenge through the design of a new class of benzyl-functionalized thionolactones (bDOTs). Guided by detailed mechanistic analyses, we find that the introduction of radical-stabilizing substituents to bDOTs enables markedly increased and tunable copolymerization reactivity with methyl methacrylate (MMA). Through iterative optimizations of the molecular structure, a specific bDOT, F-p-CF3PhDOT, is discovered to copolymerize efficiently with MMA. High molar mass deconstructable PMMA-based copolymers (dPMMA, Mn > 120 kDa) with low percentages of F-p-CF3PhDOT (1.8 and 3.8 mol%) are prepared using industrially relevant bulk free radical copolymerization conditions. The thermomechanical properties of dPMMA are similar to PMMA; however, the former is shown to degrade into low molar mass fragments (<6.5 kDa) under mild aminolysis conditions. This work presents the first example of a radical ring-opening CC capable of nearly random copolymerization with MMA without the possibility of cross-linking and provides a workflow for the mechanism-guided design of deconstructable copolymers in the future.
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Affiliation(s)
- Kwangwook Ko
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - David J Lundberg
- Department of Chemical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Alayna M Johnson
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Jeremiah A Johnson
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
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7
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Mountaki SA, Whitfield R, Parkatzidis K, Antonopoulou MN, Truong NP, Anastasaki A. Chemical recycling of bromine-terminated polymers synthesized by ATRP. RSC APPLIED POLYMERS 2024; 2:275-283. [PMID: 38525379 PMCID: PMC10955525 DOI: 10.1039/d3lp00279a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Accepted: 01/25/2024] [Indexed: 03/26/2024]
Abstract
Chemical recycling of polymers is one of the biggest challenges in materials science. Recently, remarkable achievements have been made by utilizing polymers prepared by controlled radical polymerization to trigger low-temperature depolymerization. However, in the case of atom transfer radical polymerization (ATRP), depolymerization has nearly exclusively focused on chlorine-terminated polymers, even though the overwhelming majority of polymeric materials synthesized with this method possess a bromine end-group. Herein, we report an efficient depolymerization strategy for bromine-terminated polymethacrylates which employs an inexpensive and environmentally friendly iron catalyst (FeBr2/L). The effect of various solvents and the concentration of metal salt and ligand on the depolymerization are judiciously explored and optimized, allowing for a depolymerization efficiency of up to 86% to be achieved in just 3 minutes. Notably, the versatility of this depolymerization is exemplified by its compatibility with chlorinated and non-chlorinated solvents, and both Fe(ii) and Fe(iii) salts. This work significantly expands the scope of ATRP materials compatible with depolymerization and creates many future opportunities in applications where the depolymerization of bromine-terminated polymers is desired.
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Affiliation(s)
- Stella Afroditi Mountaki
- Laboratory of Polymeric Materials, Department of Materials, ETH Zurich Vladimir-Prelog-Weg-5 8093 Zurich Switzerland
| | - Richard Whitfield
- Laboratory of Polymeric Materials, Department of Materials, ETH Zurich Vladimir-Prelog-Weg-5 8093 Zurich Switzerland
| | - Kostas Parkatzidis
- Laboratory of Polymeric Materials, Department of Materials, ETH Zurich Vladimir-Prelog-Weg-5 8093 Zurich Switzerland
| | - Maria-Nefeli Antonopoulou
- Laboratory of Polymeric Materials, Department of Materials, ETH Zurich Vladimir-Prelog-Weg-5 8093 Zurich Switzerland
| | - Nghia P Truong
- Laboratory of Polymeric Materials, Department of Materials, ETH Zurich Vladimir-Prelog-Weg-5 8093 Zurich Switzerland
| | - Athina Anastasaki
- Laboratory of Polymeric Materials, Department of Materials, ETH Zurich Vladimir-Prelog-Weg-5 8093 Zurich Switzerland
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8
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Hughes RW, Lott ME, Zastrow IS, Young JB, Maity T, Sumerlin BS. Bulk Depolymerization of Methacrylate Polymers via Pendent Group Activation. J Am Chem Soc 2024; 146:6217-6224. [PMID: 38382047 DOI: 10.1021/jacs.3c14179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2024]
Abstract
In this study, we present an efficient approach for the depolymerization of poly(methyl methacrylate) (PMMA) copolymers synthesized via conventional radical polymerization. By incorporating low mol % phthalimide ester-containing monomers during the polymerization process, colorless and transparent polymers closely resembling unfunctionalized PMMA are obtained, which can achieve >95% reversion to methyl methacrylate (MMA). Notably, our catalyst-free bulk depolymerization method exhibits exceptional efficiency, even for high-molecular-weight polymers, including ultrahigh-molecular-weight (106-107 g/mol) PMMA, where near-quantitative depolymerization is achieved. Moreover, this approach yields polymer byproducts of significantly lower molecular weight, distinguishing it from bulk depolymerization methods initiated from chain ends. Furthermore, we extend our investigation to polymethacrylate networks, demonstrating high extents of depolymerization. This innovative depolymerization strategy offers promising opportunities for the development of sustainable polymethacrylate materials, holding great potential for various applications in polymer science.
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Affiliation(s)
- Rhys W Hughes
- George & Josephine Butler Polymer Research Laboratory, Department of Chemistry, Center for Macromolecular Science & Engineering, University of Florida, Gainesville, Florida 32611, United States
| | - Megan E Lott
- George & Josephine Butler Polymer Research Laboratory, Department of Chemistry, Center for Macromolecular Science & Engineering, University of Florida, Gainesville, Florida 32611, United States
| | - Isabella S Zastrow
- George & Josephine Butler Polymer Research Laboratory, Department of Chemistry, Center for Macromolecular Science & Engineering, University of Florida, Gainesville, Florida 32611, United States
| | - James B Young
- George & Josephine Butler Polymer Research Laboratory, Department of Chemistry, Center for Macromolecular Science & Engineering, University of Florida, Gainesville, Florida 32611, United States
| | - Tanmoy Maity
- George & Josephine Butler Polymer Research Laboratory, Department of Chemistry, Center for Macromolecular Science & Engineering, University of Florida, Gainesville, Florida 32611, United States
| | - Brent S Sumerlin
- George & Josephine Butler Polymer Research Laboratory, Department of Chemistry, Center for Macromolecular Science & Engineering, University of Florida, Gainesville, Florida 32611, United States
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9
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Lohmann V, Jones GR, Truong NP, Anastasaki A. The thermodynamics and kinetics of depolymerization: what makes vinyl monomer regeneration feasible? Chem Sci 2024; 15:832-853. [PMID: 38239674 PMCID: PMC10793647 DOI: 10.1039/d3sc05143a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Accepted: 11/28/2023] [Indexed: 01/22/2024] Open
Abstract
Depolymerization is potentially a highly advantageous method of recycling plastic waste which could move the world closer towards a truly circular polymer economy. However, depolymerization remains challenging for many polymers with all-carbon backbones. Fundamental understanding and consideration of both the kinetics and thermodynamics are essential in order to develop effective new depolymerization systems that could overcome this problem, as the feasibility of monomer generation can be drastically altered by tuning the reaction conditions. This perspective explores the underlying thermodynamics and kinetics governing radical depolymerization of addition polymers by revisiting pioneering work started in the mid-20th century and demonstrates its connection to exciting recent advances which report depolymerization reaching near-quantitative monomer regeneration at much lower temperatures than seen previously. Recent catalytic approaches to monomer regeneration are also explored, highlighting that this nascent chemistry could potentially revolutionize depolymerization-based polymer recycling in the future.
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Affiliation(s)
- Victoria Lohmann
- Laboratory of Polymeric Materials, Department of Materials, ETH Zürich Vladimir-Prelog-Weg 5 8093 Zürich Switzerland
| | - Glen R Jones
- Laboratory of Polymeric Materials, Department of Materials, ETH Zürich Vladimir-Prelog-Weg 5 8093 Zürich Switzerland
| | - Nghia P Truong
- Laboratory of Polymeric Materials, Department of Materials, ETH Zürich Vladimir-Prelog-Weg 5 8093 Zürich Switzerland
- Monash Institute of Pharmaceutical Sciences, Monash University 399 Royal Parade Parkville VIC 3152 Australia
| | - Athina Anastasaki
- Laboratory of Polymeric Materials, Department of Materials, ETH Zürich Vladimir-Prelog-Weg 5 8093 Zürich Switzerland
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10
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Kuroda K, Ouchi M. Umpolung Isomerization in Radical Copolymerization of Benzyl Vinyl Ether with Pentafluorophenylacrylate Leading to Degradable AAB Periodic Copolymers. Angew Chem Int Ed Engl 2024; 63:e202316875. [PMID: 37971837 DOI: 10.1002/anie.202316875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Revised: 11/16/2023] [Accepted: 11/16/2023] [Indexed: 11/19/2023]
Abstract
This study revealed that benzyl vinyl ether (BnVE) shows a peculiar isomerization propagation in its radical copolymerization with an electron-deficient acrylate carrying a pentafluorophenyl group (PFA). The co-monomer pair inherently exhibits the cross-over propagation feature due to the large difference in the electron density. However, the radical species of PFA was found to undergo a backward isomerization to the penultimate BnVE pendant giving a benzyl radical species prior to propagation with BnVE. The isomerization brings a drastic change in the character of the growing radical species from electrophilic to nucleophilic, and thus the isomerized benzyl radial species propagates with PFA. Consequently, the two monomers were consumed in the order AAB (A: PFA; B: BnVE) and the unique periodic consumption was confirmed by the pseudo-reactivity ratios calculated by the penultimate model: r11 =0.174 and r21 =6600 for PFA (M1 ) with BnVE (M2 ). The pentafluorophenyl ester groups of the resulting copolymers are transformed into ester and amide groups by post-polymerization alcoholysis and aminolysis modifications. The unique isomerization in the AAB sequence allowed the periodic introduction of a benzyl ether structure in the backbone leading to efficient degradation under acid conditions.
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Affiliation(s)
- Keita Kuroda
- Department of Polymer Chemistry, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto, 615-8510, Japan
| | - Makoto Ouchi
- Department of Polymer Chemistry, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto, 615-8510, Japan
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11
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Bellotti V, Wang HS, Truong NP, Simonutti R, Anastasaki A. Temporal Regulation of PET-RAFT Controlled Radical Depolymerization. Angew Chem Int Ed Engl 2023; 62:e202313232. [PMID: 37814385 DOI: 10.1002/anie.202313232] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Indexed: 10/11/2023]
Abstract
A photocatalytic RAFT-controlled radical depolymerization method is introduced for precisely conferring temporal control under visible light irradiation. By regulating the deactivation of the depropagating chains and suppressing thermal initiation, an excellent temporal control was enabled, exemplified by several consecutive "on" and "off" cycles. Minimal, if any, depolymerization could be observed during the dark periods while the polymer chain-ends could be efficiently re-activated and continue to depropagate upon re-exposure to light. Notably, favoring deactivation resulted in the gradual unzipping of polymer chains and a stepwise decrease in molecular weight over time. This synthetic approach constitutes a simple methodology to modulate temporal control during the chemical recycling of RAFT-synthesized polymers while offering invaluable mechanistic insights.
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Affiliation(s)
- Valentina Bellotti
- Laboratory of Polymeric Materials, Department of Materials, ETH Zurich, Vladimir-Prelog-Weg-5, Zurich, 8093, Switzerland
- Department of Material Science, Università di Milano-Bicocca, Via Roberto Cozzi 55, Milan, 20125, Italy
| | - Hyun Suk Wang
- Laboratory of Polymeric Materials, Department of Materials, ETH Zurich, Vladimir-Prelog-Weg-5, Zurich, 8093, Switzerland
| | - Nghia P Truong
- Laboratory of Polymeric Materials, Department of Materials, ETH Zurich, Vladimir-Prelog-Weg-5, Zurich, 8093, Switzerland
| | - Roberto Simonutti
- Department of Material Science, Università di Milano-Bicocca, Via Roberto Cozzi 55, Milan, 20125, Italy
| | - Athina Anastasaki
- Laboratory of Polymeric Materials, Department of Materials, ETH Zurich, Vladimir-Prelog-Weg-5, Zurich, 8093, Switzerland
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12
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Parkatzidis K, Truong NP, Matyjaszewski K, Anastasaki A. Photocatalytic ATRP Depolymerization: Temporal Control at Low ppm of Catalyst Concentration. J Am Chem Soc 2023; 145:21146-21151. [PMID: 37737835 PMCID: PMC10557129 DOI: 10.1021/jacs.3c05632] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Indexed: 09/23/2023]
Abstract
A photocatalytic ATRP depolymerization is introduced that significantly suppresses the reaction temperature from 170 to 100 °C while enabling temporal regulation. In the presence of low-toxicity iron-based catalysts and under visible light irradiation, near-quantitative monomer recovery could be achieved (up to 90%), albeit with minimal temporal control. By employing ppm concentrations of either FeCl2 or FeCl3, the depolymerization during the dark periods could be completely eliminated, thus enabling temporal control and the possibility to modulate the rate by simply turning the light "on" and "off". Notably, our approach allowed preservation of the end-group fidelity throughout the reaction, could be carried out at high polymer loadings (up to 2M), and was compatible with various polymers and light sources. This methodology provides a facile, environmentally friendly, and temporally regulated route to chemically recycle ATRP-synthesized polymers, thus opening the door for further opportunities.
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Affiliation(s)
- Kostas Parkatzidis
- Laboratory
of Polymeric Materials, Department of Materials, ETH Zurich, Vladimir-Prelog-Weg 5, Zurich 8093, Switzerland
| | - Nghia P. Truong
- Laboratory
of Polymeric Materials, Department of Materials, ETH Zurich, Vladimir-Prelog-Weg 5, Zurich 8093, Switzerland
| | - Krzysztof Matyjaszewski
- Department
of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, Pennsylvania 15213, United States
| | - Athina Anastasaki
- Laboratory
of Polymeric Materials, Department of Materials, ETH Zurich, Vladimir-Prelog-Weg 5, Zurich 8093, Switzerland
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13
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Kumar R, Chhikara BS, Er Zeybekler S, Gupta DS, Kaur G, Chhillar M, Aggarwal AK, Rahdar A. Nanotoxicity of multifunctional stoichiometric cobalt oxide nanoparticles (SCoONPs) with repercussions toward apoptosis, necrosis, and cancer necrosis factor (TNF-α) at nano-biointerfaces. Toxicol Res (Camb) 2023; 12:716-740. [PMID: 37915472 PMCID: PMC10615831 DOI: 10.1093/toxres/tfad086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Revised: 08/11/2023] [Accepted: 09/03/2023] [Indexed: 11/03/2023] Open
Abstract
Introduction Apoptosis, necrosis, and cancer necrosis factor (TNF-a) are all impacted by the nanotoxicity of multifunctional stoichiometric cobalt oxide nanoparticles (SCoONPs) at nano-biointerfaces. The creation of multi-functional nanoparticles has had a considerable impact on the transport of drugs and genes, nanotheranostics (in-vivo imaging, concurrent diagnostics), interventions for external healing, the creation of nano-bio interfaces, and the instigation of desired changes in nanotherapeutics. Objectives The quantitative structure-activity relationships, chemical transformations, biological interactions as well as toxicological analyses are considered as main objectives. Discrete dimensions of SCoNPs-cell interaction interfaces, their characteristic physical features (size, shape, shell structure, and surface chemistry), impact on cell proliferation and differentiation are the key factors responsible for nanotoxicity. Methods The development of multi-functional nanoparticles has been significant in drug/gene delivery, nanotheranostics (in-vivo imaging, coinciding diagnostics), and external healing interventions, designing a nano-bio interface, as well as inciting desired alterations in nanotherapeutics. Every so often, the cellular uptake of multi-functional cobalt [Co, CoO, Co2(CO)8 and Co3O4] nanoparticles (SCoONPs) influences cellular mechanics and initiates numerous repercussions (oxidative stress, DNA damage, cytogenotoxicity, and chromosomal damage) in pathways, including the generation of dysregulating factors involved in biochemical transformations. Results The concerns and influences of multifunctional SCoNPs on different cell mechanisms (mitochondria impermeability, hydrolysis of ATP, the concentration of Ca2+, impaired calcium clearance, defective autophagy, apoptosis, and necrosis), and interlinked properties (adhesion, motility, and internalization dynamics, role in toxicity, surface hydrophilic and hydrophobicity, biokinetics and biomimetic behaviors of biochemical reactions) have also been summarized. SCoONPs have received a lot of interest among the nanocarriers family because of its advantageous qualities such as biodegradability, biocompatibility, nontoxicity, and nonimmunogenicity. Conclusion Various applications, such as bio-imaging, cell labeling, gene delivery, enhanced chemical stability, and increased biocompatibility, concerning apoptosis, necrosis, and nano-bio interfaces, along with suitable examples. In this analysis, the multi-functional cobalt [Co, CoO, Co2(CO)8 and Co3O4] nanoparticles (SCoNPs) intricacies (cytogenotoxicity, clastogenicity, and immunomodulatory), nanotoxicity, and associated repercussions have been highlighted and explained.
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Affiliation(s)
- Rajiv Kumar
- University of Delhi, Mall Road, New Delhi 110007, India
| | - Bhupender S Chhikara
- Department of Chemistry, Aditi Mahavidyalaya, University of Delhi, Auchandi Road, Bawana, Delhi 110039, India
| | - Simge Er Zeybekler
- Biochemistry Department, Faculty of Science, Ege University, Hastanesi 9/3A 35100 Bornova-Izmir 35100, Turkey
| | - Dhruv Sanjay Gupta
- Department of Pharmacology, SPP School of Pharmacy & Technology Management, SVKM’s NMIMS, V.L. Mehta Road, Vile Parle (W), Mumbai 400056, India
| | - Ginpreet Kaur
- Department of Pharmacology, SPP School of Pharmacy & Technology Management, SVKM’s NMIMS, V.L. Mehta Road, Vile Parle (W), Mumbai 400056, India
| | | | - Anil K Aggarwal
- Department of Chemistry, Shivaji College, University of Delhi, Ring Road, Raja Garden, New Delhi 110027, India
| | - Abbas Rahdar
- Department of Physics, Faculty of Science, University of Zabol, Sistan va Baluchestan, Zabol 538-98615, Iran
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14
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Häfliger F, Truong NP, Wang HS, Anastasaki A. Fate of the RAFT End-Group in the Thermal Depolymerization of Polymethacrylates. ACS Macro Lett 2023; 12:1207-1212. [PMID: 37615956 PMCID: PMC10515620 DOI: 10.1021/acsmacrolett.3c00418] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Accepted: 08/21/2023] [Indexed: 08/25/2023]
Abstract
Thermal RAFT depolymerization has recently emerged as a promising methodology for the chemical recycling of polymers. However, while much attention has been given to the regeneration of monomers, the fate of the RAFT end-group after depolymerization has been unexplored. Herein, we identify the dominant small molecules derived from the RAFT end-group of polymethacrylates. The major product was found to be a unimer (DP = 1) RAFT agent, which is not only challenging to synthesize using conventional single-unit monomer insertion strategies, but also a highly active RAFT agent for methyl methacrylate, exhibiting faster consumption and yielding polymers with lower dispersities compared to the original, commercially available 2-cyano-2-propyl dithiobenzoate. Solvent-derived molecules were also identified predominantly at the beginning of the depolymerization, thus suggesting a significant mechanistic contribution from the solvent. Notably, the formation of both the unimer and the solvent-derived products remained consistent regardless of the RAFT agent, monomer, or solvent employed.
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Affiliation(s)
- Florian Häfliger
- Laboratory
of Polymeric Materials, Department of Materials, ETH Zurich, Vladimir-Prelog-Weg 5, 8093 Zurich, Switzerland
| | - Nghia P. Truong
- Laboratory
of Polymeric Materials, Department of Materials, ETH Zurich, Vladimir-Prelog-Weg 5, 8093 Zurich, Switzerland
- Monash
Institute of Pharmaceutical Sciences, Monash
University, 399 Royal
Parade, Parkville, VIC 3152, Australia
| | - Hyun Suk Wang
- Laboratory
of Polymeric Materials, Department of Materials, ETH Zurich, Vladimir-Prelog-Weg 5, 8093 Zurich, Switzerland
| | - Athina Anastasaki
- Laboratory
of Polymeric Materials, Department of Materials, ETH Zurich, Vladimir-Prelog-Weg 5, 8093 Zurich, Switzerland
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15
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Whitfield R, Jones GR, Truong NP, Manring LE, Anastasaki A. Solvent-Free Chemical Recycling of Polymethacrylates made by ATRP and RAFT polymerization: High-Yielding Depolymerization at Low Temperatures. Angew Chem Int Ed Engl 2023; 62:e202309116. [PMID: 37523176 DOI: 10.1002/anie.202309116] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 07/31/2023] [Accepted: 07/31/2023] [Indexed: 08/01/2023]
Abstract
Although controlled radical polymerization is an excellent tool to make precision polymeric materials, reversal of the process to retrieve the starting monomer is far less explored despite the significance of chemical recycling. Here, we investigate the bulk depolymerization of RAFT and ATRP-synthesized polymers under identical conditions. RAFT-synthesized polymers undergo a relatively low-temperature solvent-free depolymerization back to monomer thanks to the partial in situ transformation of the RAFT end-group to macromonomer. Instead, ATRP-synthesized polymers can only depolymerize at significantly higher temperatures (>350 °C) through random backbone scission. To aid a more complete depolymerization at even lower temperatures, we performed a facile and quantitative end-group modification strategy in which both ATRP and RAFT end-groups were successfully converted to macromonomers. The macromonomers triggered a lower temperature bulk depolymerization with an onset at 150 °C yielding up to 90 % of monomer regeneration. The versatility of the methodology was demonstrated by a scalable depolymerization (≈10 g of starting polymer) retrieving 84 % of the starting monomer intact which could be subsequently used for further polymerization. This work presents a new low-energy approach for depolymerizing controlled radical polymers and creates many future opportunities as high-yielding, solvent-free and scalable depolymerization methods are sought.
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Affiliation(s)
- Richard Whitfield
- Laboratory of Polymeric Materials, D-MATL, ETH Zurich, Vladimir-Prelog-Weg-5, 8093, Zurich, Switzerland
| | - Glen R Jones
- Laboratory of Polymeric Materials, D-MATL, ETH Zurich, Vladimir-Prelog-Weg-5, 8093, Zurich, Switzerland
| | - Nghia P Truong
- Laboratory of Polymeric Materials, D-MATL, ETH Zurich, Vladimir-Prelog-Weg-5, 8093, Zurich, Switzerland
| | | | - Athina Anastasaki
- Laboratory of Polymeric Materials, D-MATL, ETH Zurich, Vladimir-Prelog-Weg-5, 8093, Zurich, Switzerland
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16
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Korpusik AB, Adili A, Bhatt K, Anatot JE, Seidel D, Sumerlin BS. Degradation of Polyacrylates by One-Pot Sequential Dehydrodecarboxylation and Ozonolysis. J Am Chem Soc 2023; 145:10480-10485. [PMID: 37155970 DOI: 10.1021/jacs.3c02497] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
We establish a synthetically convenient method to degrade polyacrylate homopolymers. Carboxylic acids are installed along the polymer backbone by partial hydrolysis of the ester side chains, and then, in a one-pot sequential procedure, the carboxylic acids are converted into alkenes and oxidatively cleaved. This process enables the robustness and properties of polyacrylates to be maintained during their usable lifetime. The ability to tune the degree of degradation was demonstrated by varying the carboxylic acid content of the polymers. This method is compatible with a wide range of polymers prepared from vinyl monomers through copolymerization of acrylic acid with different monomers including acrylates, acrylamides, and styrenics.
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Affiliation(s)
- Angie B Korpusik
- George & Josephine Butler Polymer Research Laboratory, Center for Macromolecular Science & Engineering, Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
| | - Alafate Adili
- Center for Heterocyclic Compounds, Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
| | - Kamal Bhatt
- Center for Heterocyclic Compounds, Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
| | - Jacqueline E Anatot
- George & Josephine Butler Polymer Research Laboratory, Center for Macromolecular Science & Engineering, Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
| | - Daniel Seidel
- Center for Heterocyclic Compounds, Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
| | - Brent S Sumerlin
- George & Josephine Butler Polymer Research Laboratory, Center for Macromolecular Science & Engineering, Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
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17
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Jones GR, Wang HS, Parkatzidis K, Whitfield R, Truong NP, Anastasaki A. Reversed Controlled Polymerization (RCP): Depolymerization from Well-Defined Polymers to Monomers. J Am Chem Soc 2023; 145:9898-9915. [PMID: 37127289 PMCID: PMC10176471 DOI: 10.1021/jacs.3c00589] [Citation(s) in RCA: 31] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Controlled polymerization methods are well-established synthetic protocols for the design and preparation of polymeric materials with a high degree of precision over molar mass and architecture. Exciting recent work has shown that the high end-group fidelity and/or functionality inherent in these techniques can enable new routes to depolymerization under relatively mild conditions. Converting polymers back to pure monomers by depolymerization is a potential solution to the environmental and ecological concerns associated with the ultimate fate of polymers. This perspective focuses on the emerging field of depolymerization from polymers synthesized by controlled polymerizations including radical, ionic, and metathesis polymerizations. We provide a critical review of current literature categorized according to polymerization technique and explore numerous concepts and ideas which could be implemented to further enhance depolymerization including lower temperature systems, catalytic depolymerization, increasing polymer scope, and controlled depolymerization.
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Affiliation(s)
- Glen R Jones
- Laboratory for Polymeric Materials, Department of Materials, ETH Zürich, Vladimir-Prelog-Weg 5, 8093 Zürich, Switzerland
| | - Hyun Suk Wang
- Laboratory for Polymeric Materials, Department of Materials, ETH Zürich, Vladimir-Prelog-Weg 5, 8093 Zürich, Switzerland
| | - Kostas Parkatzidis
- Laboratory for Polymeric Materials, Department of Materials, ETH Zürich, Vladimir-Prelog-Weg 5, 8093 Zürich, Switzerland
| | - Richard Whitfield
- Laboratory for Polymeric Materials, Department of Materials, ETH Zürich, Vladimir-Prelog-Weg 5, 8093 Zürich, Switzerland
| | - Nghia P Truong
- Laboratory for Polymeric Materials, Department of Materials, ETH Zürich, Vladimir-Prelog-Weg 5, 8093 Zürich, Switzerland
| | - Athina Anastasaki
- Laboratory for Polymeric Materials, Department of Materials, ETH Zürich, Vladimir-Prelog-Weg 5, 8093 Zürich, Switzerland
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18
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Bellotti V, Parkatzidis K, Wang HS, De Alwis Watuthanthrige N, Orfano M, Monguzzi A, Truong NP, Simonutti R, Anastasaki A. Light-accelerated depolymerization catalyzed by Eosin Y. Polym Chem 2023; 14:253-258. [PMID: 36760607 PMCID: PMC9843692 DOI: 10.1039/d2py01383e] [Citation(s) in RCA: 24] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Accepted: 12/13/2022] [Indexed: 12/24/2022]
Abstract
Retrieving the starting monomers from polymers synthesized by reversible deactivation radical polymerization has recently emerged as an efficient way to increase the recyclability of such materials and potentially enable their industrial implementation. To date, most methods have primarily focused on utilizing high temperatures (typically from 120 °C to 180 °C) to trigger an efficient depolymerization reaction. In this work, we show that, in the presence of Eosin Y under light irradiation, a much faster depolymerization of polymers made by reversible addition-fragmentation chain-transfer (RAFT) polymerization can be triggered even at a lower temperature (i.e. 100 °C). For instance, green light, in conjunction with ppm amounts of Eosin Y, resulted in the accelerated depolymerization of poly(methyl methacrylate) from 16% (thermal depolymerization at 100 °C) to 37% within 1 hour, and finally 80% depolymerization after 8 hours, as confirmed by both 1H-NMR and SEC analyses. The enhanced depolymerization rate was attributed to the activation of a macroCTA by Eosin Y, thus resulting in a faster macroradical generation. Notably, this method was found to be compatible with different wavelengths (e.g. blue, red and white light irradiation), solvents, and RAFT agents, thus highlighting the potential of light to significantly improve current depolymerization approaches.
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Affiliation(s)
- Valentina Bellotti
- Department of Material Science, University of Milano-Bicocca Via R. Cozzi 55 20125 Milan Italy
- Laboratory of Polymeric Materials, Department of Materials, ETH Zurich Vladimir-Prelog-Weg-5 Zurich Switzerland
| | - Kostas Parkatzidis
- Laboratory of Polymeric Materials, Department of Materials, ETH Zurich Vladimir-Prelog-Weg-5 Zurich Switzerland
| | - Hyun Suk Wang
- Laboratory of Polymeric Materials, Department of Materials, ETH Zurich Vladimir-Prelog-Weg-5 Zurich Switzerland
| | | | - Matteo Orfano
- Department of Material Science, University of Milano-Bicocca Via R. Cozzi 55 20125 Milan Italy
| | - Angelo Monguzzi
- Department of Material Science, University of Milano-Bicocca Via R. Cozzi 55 20125 Milan Italy
| | - Nghia P Truong
- Laboratory of Polymeric Materials, Department of Materials, ETH Zurich Vladimir-Prelog-Weg-5 Zurich Switzerland
| | - Roberto Simonutti
- Department of Material Science, University of Milano-Bicocca Via R. Cozzi 55 20125 Milan Italy
| | - Athina Anastasaki
- Laboratory of Polymeric Materials, Department of Materials, ETH Zurich Vladimir-Prelog-Weg-5 Zurich Switzerland
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19
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Young JB, Bowman JI, Eades CB, Wong AJ, Sumerlin BS. Photoassisted Radical Depolymerization. ACS Macro Lett 2022; 11:1390-1395. [PMID: 36469937 DOI: 10.1021/acsmacrolett.2c00603] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Controlled radical polymerization techniques enable the synthesis of polymers with predetermined molecular weights, narrow molecular weight distributions, and controlled architectures. Moreover, these polymerization approaches have been routinely shown to result in retained end-group functionality that can be reactivated to continue polymerization. However, reactivation of these end groups under conditions that instead promote depropagation is a viable route to initiate depolymerization and potentially enable closed-loop recycling from polymer to monomer. In this report, we investigate light as a trigger for thermal depolymerization of polymers prepared by reversible-addition-fragmentation chain-transfer (RAFT) polymerization. We study the role of irradiation wavelength by targeting the n → π* and π → π* electronic transitions of the thiocarbonylthio end-groups of RAFT-generated polymers to enhance depolymerization via terminal bond homolysis. Specifically, we explore depolymerization of polymers with trithiocarbonate, dithiocarbamate, and p-substituted dithiobenzoate end groups with the purpose of increasing depolymerization efficiency with light. As the wavelength decreases from the visible range to the UV range, the rate of depolymerization is dramatically increased. This method of photoassisted depolymerization allows up to 87% depolymerization efficiency within 1 h, results that may further the advancement of recyclable materials and life-cycle circularity.
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Affiliation(s)
- James B Young
- George & Josephine Butler Polymer Research Laboratory, Center for Macromolecular Science and Engineering, Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
| | - Jared I Bowman
- George & Josephine Butler Polymer Research Laboratory, Center for Macromolecular Science and Engineering, Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
| | - Cabell B Eades
- George & Josephine Butler Polymer Research Laboratory, Center for Macromolecular Science and Engineering, Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
| | - Alexander J Wong
- George & Josephine Butler Polymer Research Laboratory, Center for Macromolecular Science and Engineering, Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
| | - Brent S Sumerlin
- George & Josephine Butler Polymer Research Laboratory, Center for Macromolecular Science and Engineering, Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
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