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Closed-loop Recycling Of Plastics Enabled By Dynamic Covalent Diketoenamine Bonds
P. R. Christensen, Angelique M Scheuermann, Kathryn E. Loeffler, B. Helms
Published 2019 · Chemistry, Medicine
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Recycled plastics are low-value commodities due to residual impurities and the degradation of polymer properties with each cycle of re-use. Plastics that undergo reversible polymerization allow high-value monomers to be recovered and re-manufactured into pristine materials, which should incentivize recycling in closed-loop life cycles. However, monomer recovery is often costly, incompatible with complex mixtures and energy-intensive. Here, we show that next-generation plastics—polymerized using dynamic covalent diketoenamine bonds—allow the recovery of monomers from common additives, even in mixed waste streams. Poly(diketoenamine)s ‘click’ together from a wide variety of triketones and aromatic or aliphatic amines, yielding only water as a by-product. Recovered monomers can be re-manufactured into the same polymer formulation, without loss of performance, as well as other polymer formulations with differentiated properties. The ease with which poly(diketoenamine)s can be manufactured, used, recycled and re-used—without losing value—points to new directions in designing sustainable polymers with minimal environmental impact.It is difficult to recover materials for re-manufacturing and re-use from plastics that are compounded with colourants, fillers and flame retardants. Now, it has been shown that alternative plastics based on dynamic covalent poly(diketoenamine)s depolymerize in strong aqueous acids and enable triketone and amine monomers to be isolated and upcycled into new plastics.
This paper references
Beyond plastic waste
Ellen Macarthur (2017)
Efficient and selective degradation of polyethylenes into liquid fuels and waxes under mild conditions
Xiangqing Jia (2016)
An aromatic/aliphatic polyester prepared via ring-opening polymerisation and its remarkably selective and cyclable depolymerisation to monomer
J. P. MacDonald (2016)
$ 180 bn investment in plastic factories feeds global packaging binge
A side reaction of the Dde protecting group: migration to an unprotected lysine
K. Augustyns (1998)
Carbon Fiber Reinforced Thermoset Composite with Near 100% Recyclability
K. Yu (2016)
The Depolymerization of Poly(ethylene terephthalate) (PET) Using N-Heterocyclic Carbenes from Ionic Liquids
Nahrain E. Kamber (2010)
The future of plastics recycling
J. García (2017)
Completely recyclable biopolymers with linear and cyclic topologies via ring-opening polymerization of γ-butyrolactone.
Miao Hong (2016)
Reaction: Polymer Chemistries Enabling Cradle-to-Cradle Life Cycles for Plastics
Brett A. Helms (2016)
Kinetics of hydrolysis of poly(ethylene terephthalate) powder in sulfuric acid by a modified shrinking-core model
T. Yoshioka (2001)
Reprocessable Acid-Degradable Polycarbonate Vitrimers
Rachel L Snyder (2018)
Recyclable, Strong Thermosets and Organogels via Paraformaldehyde Condensation with Diamines
J. García (2014)
Investigation on the stability of the Dde protecting group used in peptide synthesis: migration to an unprotected lysine.
K. Augustyns (1998)
Construction of crystalline 2D covalent organic frameworks with remarkable chemical (acid/base) stability via a combined reversible and irreversible route.
S. Kandambeth (2012)
Plastics recycling with a difference
Haritz Sardon (2018)
Production, use, and fate of all plastics ever made
R. Geyer (2017)
Chemical recycling of waste plastics for new materials production
A. Rahimi (2017)
Organocatalytic depolymerization of poly(ethylene terephthalate)
K. Fukushima (2011)
Silica-Like Malleable Materials from Permanent Organic Networks
Damien Montarnal (2011)
Click Chemistry: Diverse Chemical Function from a Few Good Reactions.
H. Kolb (2001)
Chemically recyclable polymers: a circular economy approach to sustainability
Miao Hong (2017)
β-Ketoenamine-linked covalent organic frameworks capable of pseudocapacitive energy storage.
Catherine R. DeBlase (2013)
Computational and experimental investigations of one-step conversion of poly(carbonate)s into value-added poly(aryl ether sulfone)s
Gavin O. Jones (2016)
Towards Truly Sustainable Polymers: A Metal-Free Recyclable Polyester from Biorenewable Non-Strained γ-Butyrolactone.
Miao Hong (2016)
High-performance vitrimers from commodity thermoplastics through dioxaborolane metathesis
M. Röttger (2017)
Chemically Recyclable Biobased Polyurethanes
Deborah K. Schneiderman (2016)
Reprocessing and Recycling of Highly Cross-Linked Ion-Conducting Networks through Transalkylation Exchanges of C-N Bonds.
M. Obadia (2015)
Chemical Recycling of Poly(ethylene terephthalate)
George P. Karayannidis (2007)
Catalysis as an Enabling Science for Sustainable Polymers.
X. Zhang (2018)
The Quest for Converting Biorenewable Bifunctional α-Methylene-γ-butyrolactone into Degradable and Recyclable Polyester: Controlling Vinyl-Addition/Ring-Opening/Cross-Linking Pathways.
Xiaoyan Tang (2016)
Dynamic urea bond for the design of reversible and self-healing polymers
Hanze Ying (2014)
Catalyst: Design Challenges for the Future of Plastics Recycling
J. Garcia (2016)
Highly stable keto-enamine salicylideneanilines.
Jonathan H. Chong (2003)
Rehealable, fully recyclable, and malleable electronic skin enabled by dynamic covalent thermoset nanocomposite
Zhanan Zou (2018)
Advanced chemical recycling of poly(ethylene terephthalate) through organocatalytic aminolysis
K. Fukushima (2013)
Mechanically activated, catalyst-free polyhydroxyurethane vitrimers.
David J Fortman (2015)
A synthetic polymer system with repeatable chemical recyclability
Jian-Bo Zhu (2018)
50th Anniversary Perspective: There Is a Great Future in Sustainable Polymers
Deborah K. Schneiderman (2017)
Repairable Woven Carbon Fiber Composites with Full Recyclability Enabled by Malleable Polyimine Networks.
Philip Taynton (2016)
Dynamic covalent chemistry.
S. Rowan (2002)
Malleable and Recyclable Poly(urea-urethane) Thermosets bearing Hindered Urea Bonds.
Y. Zhang (2016)
Vinylogous Urethane Vitrimers
Wim Denissen (2015)
Mechanistic aspects of the direct C-acylation of cyclic 1,3-diones with various unactivated carboxylic acids
Michal Kohout (2015)
This paper is referenced by
Synthesis and characterization of easily degradable acrylate-epoxy resin with superior dielectric properties and high transmittance
Maoping Lu (2020)
Fluorodynamers displaying tunable fluorescence on constitutional exchanges in solution and at solid film-solution interface.
Mingran Si (2020)
Dynamic multiphase semi-crystalline polymers based on thermally reversible pyrazole-urea bonds
W. Liu (2019)
Facile synthesis of “digestible”, rigid-and-flexible, bio-based building block for high-performance degradable thermosetting plastics
Binbo Wang (2020)
Stimuli‐Mild, Robust, Commercializable Polyurethane‐Urea Vitrimer Elastomer via N,N′‐Diaryl Urea Crosslinking
D. Zhang (2020)
Reprocessable Cross-Linked Polymer Networks: Are Associative Exchange Mechanisms Desirable?
Benjamin R. Elling (2020)
Development of a completely recyclable glass fiber‐reinforced epoxy thermoset composite
M. Lejeail (2021)
Robust, high-barrier, and fully recyclable cellulose-based plastic replacement enabled by a dynamic imine polymer
Zhiping Su (2020)
Dynamic covalent polymers for biomedical applications
Y. Zhang (2020)
Synthesis of novel polycarbonyl Schiff bases by ring-opening reaction of ethyl 5-acyl-4-pyrone-2-carboxylates with primary mono- and diamines
D. L. Obydennov (2019)
High production-yield solid-state carbon dots with tunable photoluminescence for white/multi-color light-emitting diodes
Haoqiang Song (2019)
Microplasmas for Advanced Materials and Devices.
Wei-Hung Chiang (2019)
Sustainable synthesis of 1,2,3,4-cyclohexanetetracarboxylate from sugar-derived carboxylic acids.
R. Lu (2020)
Dynamic polymer network points the way to truly recyclable plastics
Coralie Jehanno (2019)
Plastics in the US: toward a material flow characterization of production, markets and end of life
Martin C Heller (2020)
Modeling the dissolution of thermosetting polymers and composites via solvent assisted exchange reactions
C. Hamel (2020)
Chemical recycling to monomer for an ideal, circular polymer economy
G. Coates (2020)
Dynamic Bonds Mediate π-π Interaction via Phase Locking Effect for Enhanced Heat Resistant Thermoplastic Polyurethane
Yue Lai (2020)
Production and closed-loop recycling of biomass-based malleable materials
Zhiping Su (2020)
A unifying review of polymer networks: from rubbers and gels to porous frameworks
Yuwei Gu (2020)
Thermoplastic PLA-LCP Composites: A Route toward Sustainable, Reprocessable, and Recyclable Reinforced Materials
Gijs W. de Kort (2020)
Plastics as a materials system in a circular economy
D. Bucknall (2020)
Tuning polymer properties of non-covalent crosslinked PDMS by varying supramolecular interaction strength
Brigitte A. G. Lamers (2020)
Dihydrazone-based dynamic covalent epoxy networks with high creep resistance, controlled degradability, and intrinsic antibacterial properties from bioresources
Xiwei Xu (2020)
Cleavable comonomers enable degradable, recyclable thermoset plastics
P. Shieh (2020)
Influence of the polymer matrix on the viscoelastic behaviour of vitrimers
Yann Spiesschaert (2020)
Polar-Functionalized, Crosslinkable, Self-Healing and Photoresponsive Polyolefins.
C. Zou (2019)
Reprocessable, Reworkable, and Mechanochromic Polyhexahydrotriazine Thermoset with Multiple Stimulus Responsiveness
L. Chen (2020)
Chemical recycling of polyenaminones by transamination reaction via amino–enaminone polymerisation/depolymerisation
A. Zupanc (2019)
Toward Stimuli-Responsive Dynamic Thermosets through Continuous Development and Improvements in Covalent Adaptable Networks (CANs).
M. Podgórski (2020)
Conductive vitrimer nanocomposites enable advanced and recyclable thermo-sensitive materials
S. Wang (2020)
Biodegradable polymers: a cure for the planet, but a long way to go
Guang-Zhong Yin (2020)See more