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Published on: October 17, 2016
Research Progress in the Preparation of Lactide
Meiqi Tian1, Yingjian Zhou2, Junhao Wang1
1Department of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029, China.
Polymers
|June 26, 2026
Summary
This review analyzes lactide synthesis for sustainable polylactic acid (PLA) production. It compares one-step and two-step routes, highlighting challenges and future directions for efficient, stereochemically pure monomer generation.
Area of Science:
- Polymer Chemistry
- Sustainable Materials Science
- Organic Synthesis
Background:
- Polylactic acid (PLA) is a biodegradable polymer with growing demand, derived from renewable resources.
- Lactide is the crucial cyclic monomer for PLA production via ring-opening polymerization (ROP).
- Current lactide synthesis methods face challenges in stereochemical control, side reactions, and energy efficiency.
Purpose of the Study:
- To systematically review and analyze recent advancements in lactide synthesis.
- To compare the primary industrial routes for lactide production: one-step and two-step processes.
- To identify challenges, mechanisms, and future research directions for sustainable lactide manufacturing.
Main Methods:
- Analysis of the one-step process: direct dehydration-cyclization of lactic acid (LA).
- Analysis of the two-step process: LA prepolymerization followed by oligomer depolymerization/cyclization.
- Discussion of reaction mechanisms, side reactions (racemization, transesterification), catalysts, and separation strategies.
Main Results:
- The one-step route shows potential for process integration and energy efficiency.
- The two-step route offers superior control over stereochemical purity and process stability.
- Key challenges include managing side reactions like racemization and deep polycondensation.
Conclusions:
- Both one-step and two-step lactide synthesis routes have distinct advantages and disadvantages.
- Optimizing catalytic systems and reaction-separation coupling is crucial for efficient production.
- Future research should focus on green catalysts, process intensification, and overall sustainability.
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