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Title: Closed-loop recycling of plastics enabled by dynamic covalent diketoenamine bonds

Abstract

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.

Authors:
ORCiD logo [1];  [2];  [1]; ORCiD logo [3]
  1. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). The Molecular Foundry
  2. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). The Molecular Foundry; Univ. of California, Berkeley, CA (United States). Dept. of Chemistry
  3. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). The Molecular Foundry and Materials Science Div.
Publication Date:
Research Org.:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1596671
Grant/Contract Number:  
AC02-05CH11231
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Nature Chemistry
Additional Journal Information:
Journal Volume: 11; Journal Issue: 5; Journal ID: ISSN 1755-4330
Publisher:
Nature Publishing Group
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; Polymer synthesis; Sustainability

Citation Formats

Christensen, Peter R., Scheuermann, Angelique M., Loeffler, Kathryn E., and Helms, Brett A. Closed-loop recycling of plastics enabled by dynamic covalent diketoenamine bonds. United States: N. p., 2019. Web. doi:10.1038/s41557-019-0249-2.
Christensen, Peter R., Scheuermann, Angelique M., Loeffler, Kathryn E., & Helms, Brett A. Closed-loop recycling of plastics enabled by dynamic covalent diketoenamine bonds. United States. doi:10.1038/s41557-019-0249-2.
Christensen, Peter R., Scheuermann, Angelique M., Loeffler, Kathryn E., and Helms, Brett A. Mon . "Closed-loop recycling of plastics enabled by dynamic covalent diketoenamine bonds". United States. doi:10.1038/s41557-019-0249-2.
@article{osti_1596671,
title = {Closed-loop recycling of plastics enabled by dynamic covalent diketoenamine bonds},
author = {Christensen, Peter R. and Scheuermann, Angelique M. and Loeffler, Kathryn E. and Helms, Brett A.},
abstractNote = {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.},
doi = {10.1038/s41557-019-0249-2},
journal = {Nature Chemistry},
issn = {1755-4330},
number = 5,
volume = 11,
place = {United States},
year = {2019},
month = {4}
}

Journal Article:
Free Publicly Available Full Text
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Cited by: 23 works
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    Works referencing / citing this record:

    Rehealable, fully recyclable, and malleable electronic skin enabled by dynamic covalent thermoset nanocomposite
    journal, February 2018


    Chemical Recycling of Poly(ethylene terephthalate)
    journal, April 1997

    • Paszun, Daniel; Spychaj, Tadeusz
    • Industrial & Engineering Chemistry Research, Vol. 36, Issue 4
    • DOI: 10.1021/ie960563c

    Efficient and selective degradation of polyethylenes into liquid fuels and waxes under mild conditions
    journal, June 2016

    • Jia, Xiangqing; Qin, Chuan; Friedberger, Tobias
    • Science Advances, Vol. 2, Issue 6
    • DOI: 10.1126/sciadv.1501591

    Plastics recycling with a difference
    journal, April 2018


    Kinetics of Hydrolysis of Poly(ethylene terephthalate) Powder in Sulfuric Acid by a Modified Shrinking-Core Model
    journal, January 2001

    • Yoshioka, Toshiaki; Motoki, Tsutomu; Okuwaki, Akitsugu
    • Industrial & Engineering Chemistry Research, Vol. 40, Issue 1
    • DOI: 10.1021/ie000592u

    High-performance vitrimers from commodity thermoplastics through dioxaborolane metathesis
    journal, April 2017


    β-Ketoenamine-Linked Covalent Organic Frameworks Capable of Pseudocapacitive Energy Storage
    journal, October 2013

    • DeBlase, Catherine R.; Silberstein, Katharine E.; Truong, Thanh-Tam
    • Journal of the American Chemical Society, Vol. 135, Issue 45
    • DOI: 10.1021/ja409421d

    Mechanistic aspects of the direct C-acylation of cyclic 1,3-diones with various unactivated carboxylic acids
    journal, May 2015


    50th Anniversary Perspective : There Is a Great Future in Sustainable Polymers
    journal, May 2017


    Completely recyclable biopolymers with linear and cyclic topologies via ring-opening polymerization of γ-butyrolactone
    journal, November 2015

    • Hong, Miao; Chen, Eugene Y. -X.
    • Nature Chemistry, Vol. 8, Issue 1
    • DOI: 10.1038/nchem.2391

    Construction of Crystalline 2D Covalent Organic Frameworks with Remarkable Chemical (Acid/Base) Stability via a Combined Reversible and Irreversible Route
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    • Kandambeth, Sharath; Mallick, Arijit; Lukose, Binit
    • Journal of the American Chemical Society, Vol. 134, Issue 48
    • DOI: 10.1021/ja308278w

    Reprocessing and Recycling of Highly Cross-Linked Ion-Conducting Networks through Transalkylation Exchanges of C–N Bonds
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    • Obadia, Mona M.; Mudraboyina, Bhanu P.; Serghei, Anatoli
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    • DOI: 10.1021/jacs.5b02653

    Dynamic urea bond for the design of reversible and self-healing polymers
    journal, February 2014

    • Ying, Hanze; Zhang, Yanfeng; Cheng, Jianjun
    • Nature Communications, Vol. 5, Issue 1
    • DOI: 10.1038/ncomms4218

    Carbon Fiber Reinforced Thermoset Composite with Near 100% Recyclability
    journal, July 2016

    • Yu, Kai; Shi, Qian; Dunn, Martin L.
    • Advanced Functional Materials, Vol. 26, Issue 33
    • DOI: 10.1002/adfm.201602056

    Repairable Woven Carbon Fiber Composites with Full Recyclability Enabled by Malleable Polyimine Networks
    journal, February 2016

    • Taynton, Philip; Ni, Huagang; Zhu, Chengpu
    • Advanced Materials, Vol. 28, Issue 15
    • DOI: 10.1002/adma.201505245

    Reaction: Polymer Chemistries Enabling Cradle-to-Cradle Life Cycles for Plastics
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    Chemically Recyclable Biobased Polyurethanes
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    Silica-Like Malleable Materials from Permanent Organic Networks
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    Highly Stable Keto-Enamine Salicylideneanilines
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    • Chong, Jonathan H.; Sauer, Marc; Patrick, Brian O.
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    • DOI: 10.1073/pnas.1600924113

    The future of plastics recycling
    journal, November 2017


    Investigation on the stability of the Dde protecting group used in peptide synthesis: migration to an unprotected lysine1
    journal, February 1998


    Vinylogous Urethane Vitrimers
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    • Denissen, Wim; Rivero, Guadalupe; Nicolaÿ, Renaud
    • Advanced Functional Materials, Vol. 25, Issue 16
    • DOI: 10.1002/adfm.201404553

    Recyclable, Strong Thermosets and Organogels via Paraformaldehyde Condensation with Diamines
    journal, May 2014


    Towards Truly Sustainable Polymers: A Metal-Free Recyclable Polyester from Biorenewable Non-Strained γ-Butyrolactone
    journal, March 2016

    • Hong, Miao; Chen, Eugene Y. -X.
    • Angewandte Chemie International Edition, Vol. 55, Issue 13
    • DOI: 10.1002/anie.201601092

    Reprocessable Acid-Degradable Polycarbonate Vitrimers
    journal, January 2018


    Mechanically Activated, Catalyst-Free Polyhydroxyurethane Vitrimers
    journal, November 2015

    • Fortman, David J.; Brutman, Jacob P.; Cramer, Christopher J.
    • Journal of the American Chemical Society, Vol. 137, Issue 44
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    journal, July 2016

    • Zhang, Yanfeng; Ying, Hanze; Hart, Kevin R.
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    Chemical recycling of waste plastics for new materials production
    journal, June 2017