Designing Closed-Loop Chemically Recyclable Polyurethane Foam

Polyurethane Foams (PUFs) are widely used in various industrial applications. However, most commercial PUFs are fossil-derived and their non-degradability and non-reprocessability raise significant environmental challenges. Accordingly, the development of sustainable PUFs is of urgent importance. In this study, we synthesized a chemically recyclable polyol based on poly(dihydrofuran) (PDHF) through ring-opening metathesis polymerization (ROMP) followed by thiol-ene functionalization. The resulting polyol was subsequently employed in an  isocyanate-based foaming process to produce flexible PUFs. The resulting foams exhibited physical properties comparable to those of conventional PUFs. Furthermore, the monomer was efficiently recovered in high yield and high purity via ring-closing depolymerization using a reactive distillation process. This study demonstrates a closed-loop recycling strategy for PUFs and provides a potential pathway toward sustainable polyurethane systems.