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Updated: Jan 8, 2026
10:22
Designed for Molecular Recycling: A Lignin-Derived Semi-aromatic Biobased Polymer
Published on: November 30, 2020
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Spirosalen-scandium catalysts enable the epimerization-tolerant closed-loop circularity of poly(l-lactic acid)
Yu-Ting Huang1, Hao-Yi Huang1, Min Xie1
1National Engineering Laboratory of Eco-Friendly Polymeric Materials (Sichuan), College of Chemistry, Sichuan University, Chengdu 610064, China.
National Science Review
|December 12, 2025
Summary
This study introduces a new chemical recycling strategy for poly(l-lactic acid) (PLLA). It uses a scandium catalyst to create stereogradient block PLA, preserving original material properties and enabling sustainable plastic recycling.
Area of Science:
- Polymer Chemistry
- Sustainable Materials
- Catalysis
Background:
- Poly(l-lactic acid) (PLLA) is a sustainable plastic with limited chemical recycling options.
- Epimerization of l-lactide to meso-lactide during recycling degrades PLLA's material performance.
Purpose of the Study:
- To develop an epimerization-tolerant strategy for PLLA chemical recycling.
- To achieve stereoselective and sequence-controlled polymerization of PLLA.
Main Methods:
- Utilized robust spirosalen-scandium complexes (Sc) for catalysis.
- Employed Sc catalytic system for stereoselective polymerization of l-lactide in the presence of meso-lactide.
Main Results:
- Successfully synthesized stereogradient block poly(lactic acid) P(meso-LA-grad-LLA).
- The process circumvents epimerization, preserving the original material properties of PLLA.
- Demonstrated heteroselectivity towards rac-LA and syndioselectivity for meso-LA polymerization.
Conclusions:
- Developed an innovative, epimerization-tolerant chemical recycling pathway for PLLA.
- This strategy offers a route to next-generation chemical recyclable polymers.
- Maintained the high material performance of the original PLLA through controlled polymerization.
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