Phenylimino-pyridine-phenolate Zinc Complexes for Polylactide Synthesis and Chemical Recycling to Monomers

Jia-Yue Li; Ming-Qian Wang; Zhi-Qiang Ding; He He; Xin-Cui Shi; Bin Wang

doi:10.1007/s10118-025-3263-4

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Phenylimino-pyridine-phenolate Zinc Complexes for Polylactide Synthesis and Chemical Recycling to Monomers

RESEARCH ARTICLE | Updated：2025-07-14

- Phenylimino-pyridine-phenolate Zinc Complexes for Polylactide Synthesis and Chemical Recycling to Monomers
- Chinese Journal of Polymer Science Vol. 43, Issue 6, Pages: 914-923(2025)
- Affiliations：
  
  a.Tianjin Key Laboratory of Composite & Functional Materials, School of Materials Science and Engineering, Tianjin University, Tianjin 300350, China
  b.School of Chemistry and Environmental Engineering, Changchun University of Science and Technology, Changchun 130012, China
- Author bio：
  
  xcsh@cust.edu.cn (X.C.S.)
  binwang@tju.edu.cn (B.W.)
- Funds：
- DOI：10.1007/s10118-025-3263-4
  CLC： M
- Received：06 September 2024，
  
  Revised：2024-11-05，
  
  Accepted：06 November 2024，
  
  Online First：25 January 2025，
  
  Published：20 May 2025
- Accepted：
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Li, J. Y.; Wang, M. Q.; Ding, Z. Q.; He, H.; Shi, X. C.; Wang, B. Phenylimino-pyridine-phenolate zinc complexes for polylactide synthesis and chemical recycling to monomers. Chinese J. Polym. Sci. 2025, 43, 914–923

Jia-Yue Li, Ming-Qian Wang, Zhi-Qiang Ding, et al. Phenylimino-pyridine-phenolate Zinc Complexes for Polylactide Synthesis and Chemical Recycling to Monomers[J]. Chinese Journal of Polymer Science, 2025, 43(6): 914-923.
Li, J. Y.; Wang, M. Q.; Ding, Z. Q.; He, H.; Shi, X. C.; Wang, B. Phenylimino-pyridine-phenolate zinc complexes for polylactide synthesis and chemical recycling to monomers. Chinese J. Polym. Sci. 2025, 43, 914–923 DOI： 10.1007/s10118-025-3263-4.

Jia-Yue Li, Ming-Qian Wang, Zhi-Qiang Ding, et al. Phenylimino-pyridine-phenolate Zinc Complexes for Polylactide Synthesis and Chemical Recycling to Monomers[J]. Chinese Journal of Polymer Science, 2025, 43(6): 914-923. DOI： 10.1007/s10118-025-3263-4.

摘要

We designed and synthesized phenylimino-pyridine-phenolate zinc complexes for efficient polylactide synthesis. The activity of preferred catalyst is comparable to those of commercial stannous octanoate and can be used in the direct depolymerization of PLA to recover L-LA monomer.

Abstract

Poly(

-lactide) (PLLA) is one of the best candidates as a bio-based plastic material for circular economy because of its biodegradability

sustainability

recyclability

and good thermal and mechanical properties. The industrial production of PLLA is mainly from tin(II) 2-ethylhexanoate [Sn(Oct)

]

-catalyzed ring-opening polymerization (ROP) of

-LA in melt and bulk conditions at high temperatures (150−200 °C). Despite the huge efforts devoted to the development of organometallics with low toxicity and many highly active catalysts under mild laboratory conditions

very few candidates can compete with Sn(Oct)

under industrially relevant conditions. Herein

we report novel zinc complexes bearing phenylimino-pyridine-phenolate ligands as efficient catalysts for

-LA polymerization under both mild and industrially relevant conditions

with a turnover frequency as high as 6200 h

−1

. The best performing catalyst competed well with Sn(Oct)

under industrial conditions and afforded colorless and semicrystalline PLLA. In addition

preliminary depolymerization experiments suggested that the new catalysts can also be used for the chemical recycling of commercial PLLA directly to

-LA with high selectivity under bulk and melt conditions.

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references

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