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Updated: Jul 4, 2026
11:49
Synthesis of Soft Polysiloxane-urea Elastomers for Intraocular Lens Application
Published on: March 8, 2019
Solvent-, Catalyst-, and Heating-Free Mechanochemical Depolymerization of Polyurethane
Soonhyuk Cha1, Gyeongjin Kwon1, Byeong-Su Kim1
1Department of Chemistry, Yonsei University, Seoul, Republic of Korea.
Chemsuschem
|July 2, 2026
Summary
Researchers developed a new, sustainable method to recycle polyurethane (PU) waste. This solvent-free, catalyst-free, and heating-free mechanochemical process efficiently recovers polyols from PU products using only sodium hydroxide.
Area of Science:
- Polymer Chemistry
- Materials Science
- Sustainable Chemistry
Background:
- Polyurethane (PU) is a versatile synthetic polymer known for its durability.
- The cross-linked structure of PU poses recycling challenges, limiting sustainable waste management.
- Conventional depolymerization methods are often energy-intensive and require harsh conditions.
Purpose of the Study:
- To develop a sustainable and scalable method for polyurethane depolymerization.
- To achieve efficient polyol recovery from PU waste under ambient conditions.
- To explore the potential of mechanochemistry for polymer valorization.
Main Methods:
- A solvent-, catalyst-, and heating-free mechanochemical method using sodium hydroxide.
- Optimization of reaction parameters using a model urethane compound.
- Monitoring reaction progress via Nuclear Magnetic Resonance (NMR) and High-Performance Liquid Chromatography (HPLC).
Main Results:
- Successful depolymerization of commercial PU products, including kitchen sponges and insulation foam.
- Achieved up to 69% polyol recovery within 3 hours of ball milling.
- Demonstrated efficient urethane bond cleavage under ambient conditions.
Conclusions:
- Mechanochemical depolymerization offers a practical and sustainable route for polyol recovery from PU waste.
- This solid-state approach significantly reduces solvent usage and simplifies the recycling process.
- Highlights the potential of mechanochemistry for sustainable polymer valorization and circular economy initiatives.
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