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

Journal Article · · Nature Chemistry
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.

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.

Research Organization:
Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
Sponsoring Organization:
USDOE Office of Science (SC); USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
Grant/Contract Number:
AC02-05CH11231
OSTI ID:
1596671
Journal Information:
Nature Chemistry, Journal Name: Nature Chemistry Journal Issue: 5 Vol. 11; ISSN 1755-4330
Publisher:
Nature Publishing GroupCopyright Statement
Country of Publication:
United States
Language:
English

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