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Semi-Crystalline and Amorphous Polyesters Derived from Biobased Tri-Aromatic Dicarboxylates and Containing Cleavable Acylhydrazone Units for Short-Loop Chemical Recycling

Valsange, Nitin G. LU ; Natal Lima de Menezes, Rafael LU orcid ; Warlin, Niklas LU ; Mankar, Smita V. LU ; Rehnberg, Nicola LU orcid ; Zhang, Baozhong LU and Jannasch, Patric LU orcid (2024) In Macromolecules 57(6). p.2868-2878
Abstract
Recycling polymers by site-specific scission into short-chain oligomers/polymers, followed by recoupling these to form the original polymer presents an energetically more favorable shorter-loop chemical recycling in comparison to recycling into monomers. Here, we present the synthesis and polymerization of triaromatic diesters to prepare polyesters with acylhydrazone units as weak structural links. Two diester monomers were prepared by combining methyl 5-chloromethyl-2-furoate, obtained from 5-chloromethylfurfural (CMF), with potentially biobased hydroquinone and resorcinol, respectively. The two diesters having a central phenyl ring flanked by two furan rings were polymerized with 1,6-hexanediol and 1,4-butanediol, respectively, together... (More)
Recycling polymers by site-specific scission into short-chain oligomers/polymers, followed by recoupling these to form the original polymer presents an energetically more favorable shorter-loop chemical recycling in comparison to recycling into monomers. Here, we present the synthesis and polymerization of triaromatic diesters to prepare polyesters with acylhydrazone units as weak structural links. Two diester monomers were prepared by combining methyl 5-chloromethyl-2-furoate, obtained from 5-chloromethylfurfural (CMF), with potentially biobased hydroquinone and resorcinol, respectively. The two diesters having a central phenyl ring flanked by two furan rings were polymerized with 1,6-hexanediol and 1,4-butanediol, respectively, together with controlled amounts of monofunctional ethyl levulinate to form telechelic ketone-terminated polyesters. Subsequent reactions of these telechelic polyesters with adipic dihydrazide yielded corresponding chain-extended polyesters with increased molecular weights ([η] = 0.29−0.52 dL g−1) with acylhydrazone units in the backbone. Thermogravimetric analysis showed a high thermal stability of the polyesters with thermal decomposition only above 275 °C. The polyesters containing the linear hydroquinone units were found to be semicrystalline materials with melting points at 158 and 192 °C, respectively, while those containing the kinked resorcinol units were fully amorphous with glass transition temperatures at 35 and 44 °C, respectively. Initial investigations of the chemical recyclability of the polyesters demonstrated that acylhydrazone units could be selectively cleaved to recover the original telechelic ketone-terminated polyesters, which could again be chain-extended to obtain a recycled polymer with molecular weights and properties very similar to those of the original polymer.
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author
; ; ; ; ; and
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Macromolecules
volume
57
issue
6
pages
11 pages
publisher
The American Chemical Society (ACS)
external identifiers
  • scopus:85187189691
ISSN
0024-9297
DOI
10.1021/acs.macromol.3c02299
language
English
LU publication?
yes
id
3b742382-3c0d-4e3d-afa0-6ca5ab010691
date added to LUP
2023-11-09 19:25:13
date last changed
2024-04-03 04:01:32
@article{3b742382-3c0d-4e3d-afa0-6ca5ab010691,
  abstract     = {{Recycling polymers by site-specific scission into short-chain oligomers/polymers, followed by recoupling these to form the original polymer presents an energetically more favorable shorter-loop chemical recycling in comparison to recycling into monomers. Here, we present the synthesis and polymerization of triaromatic diesters to prepare polyesters with acylhydrazone units as weak structural links. Two diester monomers were prepared by combining methyl 5-chloromethyl-2-furoate, obtained from 5-chloromethylfurfural (CMF), with potentially biobased hydroquinone and resorcinol, respectively. The two diesters having a central phenyl ring flanked by two furan rings were polymerized with 1,6-hexanediol and 1,4-butanediol, respectively, together with controlled amounts of monofunctional ethyl levulinate to form telechelic ketone-terminated polyesters. Subsequent reactions of these telechelic polyesters with adipic dihydrazide yielded corresponding chain-extended polyesters with increased molecular weights ([η] = 0.29−0.52 dL g<sup>−1</sup>) with acylhydrazone units in the backbone. Thermogravimetric analysis showed a high thermal stability of the polyesters with thermal decomposition only above 275 °C. The polyesters containing the linear hydroquinone units were found to be semicrystalline materials with melting points at 158 and 192 °C, respectively, while those containing the kinked resorcinol units were fully amorphous with glass transition temperatures at 35 and 44 °C, respectively. Initial investigations of the chemical recyclability of the polyesters demonstrated that acylhydrazone units could be selectively cleaved to recover the original telechelic ketone-terminated polyesters, which could again be chain-extended to obtain a recycled polymer with molecular weights and properties very similar to those of the original polymer.<br/>}},
  author       = {{Valsange, Nitin G. and Natal Lima de Menezes, Rafael and Warlin, Niklas and Mankar, Smita V. and Rehnberg, Nicola and Zhang, Baozhong and Jannasch, Patric}},
  issn         = {{0024-9297}},
  language     = {{eng}},
  number       = {{6}},
  pages        = {{2868--2878}},
  publisher    = {{The American Chemical Society (ACS)}},
  series       = {{Macromolecules}},
  title        = {{Semi-Crystalline and Amorphous Polyesters Derived from Biobased Tri-Aromatic Dicarboxylates and Containing Cleavable Acylhydrazone Units for Short-Loop Chemical Recycling}},
  url          = {{http://dx.doi.org/10.1021/acs.macromol.3c02299}},
  doi          = {{10.1021/acs.macromol.3c02299}},
  volume       = {{57}},
  year         = {{2024}},
}