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Updated: Sep 3, 2025
10:22
Designed for Molecular Recycling: A Lignin-Derived Semi-aromatic Biobased Polymer
Published on: November 30, 2020
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Recovery of Green Polyols from Rigid Polyurethane Waste by Catalytic Depolymerization
Rafael Miguel-Fernández1, Izotz Amundarain1, Asier Asueta1
1GAIKER Technology Centre, Basque Research and Technology Alliance (BRTA), Parque Tecnológico de Bizkaia, Edificio 202, 48170 Zamudio, Spain.
Polymers
|July 27, 2022
Summary
This study presents a chemical recycling method for rigid polyurethane foam (RPUF) waste, converting it into high-purity green polyols. These recycled polyols can partially replace commercial ones in new RPUF synthesis.
Area of Science:
- Polymer Chemistry
- Materials Science
- Sustainable Chemistry
Background:
- Rigid Polyurethane Foam (RPUF) waste is predominantly landfilled, with limited mechanical recycling.
- Mechanical recycling of RPUF involves size reduction to a fine powder for use as filler.
- Chemical recycling offers a more advanced approach to valorize RPUF waste.
Purpose of the Study:
- To develop a chemical recycling process for rigid polyurethane foam (RPUF) waste.
- To obtain high-purity green polyols from RPUF through solvolysis.
- To evaluate the feasibility of using recycled polyols in new RPUF formulations.
Main Methods:
- Chemical depolymerization (solvolysis) of RPUF waste using a solvent and catalyst.
- Purification of glycolysis products via vacuum distillation, centrifugation, and acid water treatment.
- Characterization of recycled polyols' physicochemical properties (hydroxyl value, acid value, molecular weight, viscosity) and thermal stability (FTIR, TGA).
Main Results:
- Optimal process conditions were established for catalytic glycolysis of RPUF waste.
- High-purity green polyols were successfully obtained from both aliphatic and aromatic RPUF.
- Recycled polyols were characterized, showing suitable properties for potential reuse.
- Partial substitution (up to 15 wt.%) of commercial polyols with recycled polyols in RPUF synthesis was demonstrated.
Conclusions:
- Chemical recycling via solvolysis is an effective method for valorizing RPUF waste.
- The obtained green polyols possess properties suitable for partial substitution in new polyurethane production.
- This approach contributes to a circular economy for polyurethane materials.
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