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Updated: Jun 9, 2026
13:46
A Facile and Eco-friendly Route to Fabricate Poly(Lactic Acid) Scaffolds with Graded Pore Size
Published on: October 17, 2016
Robust, Thermally Stable and Impurity-Tolerant Aluminum-Based Catalyst System for Polylactide Production under
Ze-Bin Wang1,2, Mingqian Wang2, Zhiqiang Ding2
1College of Science, Shenyang University of Chemical Technology, Shenyang 110142, China.
Polymer Science & Technology (Washington, D.C.)
|June 8, 2026
Summary
New aluminum catalysts enable efficient, high-temperature ring-opening polymerization of l-lactide to produce polylactide. These catalysts offer improved control and tolerance to impurities, presenting a safer alternative for industrial applications.
Area of Science:
- Polymer Chemistry
- Organometallic Chemistry
- Materials Science
Background:
- Ring-opening polymerization of l-lactide (l-LA) is key for producing polylactide (PLA) from renewable resources.
- The current industrial standard catalyst, tin-(II) bis-(2-ethylhexanoate) [Sn(Oct)2], is cytotoxic.
- Existing benign catalysts often require low temperatures and solution-based processes, lacking robustness for industrial needs.
Purpose of the Study:
- To design and synthesize novel, low-toxicity aluminum-based catalysts for industrial l-LA polymerization.
- To develop catalysts that are thermally stable, protonic agent-tolerant, and effective under melt/bulk conditions.
- To investigate structure-catalytic performance relationships for optimizing PLA production.
Main Methods:
- Synthesis of tetracoordinate aluminum methyl complexes featuring (amidoalkyl)-pyridine-phenolate (AmPyPh) pincers.
- Catalytic evaluation of these complexes in l-LA polymerization under industrial-relevant conditions (150-180 °C, melt/bulk).
- Density functional theory (DFT) calculations to elucidate structure-catalytic performance relationships.
Main Results:
- The synthesized (AmPyPh)-AlMe complexes effectively catalyzed l-LA polymerization at high temperatures (150-180 °C).
- These catalysts demonstrated suppression of epimerization, yielding semicrystalline PLLA with controlled molecular weight and narrow distribution.
- Performance was comparable to Sn(Oct)2, with superior control and tolerance to impurities like benzyl alcohol and technical grade l-LA.
Conclusions:
- Novel (AmPyPh)-AlMe complexes represent a promising, safer alternative to Sn(Oct)2 for industrial PLA production.
- These catalysts exhibit high activity, thermal stability, and tolerance to impurities under demanding conditions.
- The developed catalysts offer enhanced control over polymerization, leading to high-quality semicrystalline PLLA.
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