Flow Reactor Synthesis of Bio-Based Polyol from Soybean Oil for the Production of Rigid Polyurethane Foam

In this study, a complex ring-opening agent including benzoic acid pentaerythritol ester bearing an aromatic group and pentaerythritol monolaurate bearing a pendant chain was applied in the ring-opening process. Bio-based polyols were obtained through epoxidation in the fixed-bed flow reactor and ring-opening reaction in the flask. Integration of flow chemistry and batch reaction promoted the production of bio-based polyols. The resulting rigid polyurethane foams (PUF) were characterized by scanning electron microscopy, thermogravimetry analysis, and dynamic thermomechanical analysis. Higher mechanical strength and lower thermal conductivity coefficient were obtained when the combination of aromatic alcohol and aliphatic alcohol was applied in the preparation of rigid PUF. Meanwhile, better dimensional stability and higher glass-transition temperature were detected in PUF-bio-3/7. A series of research results demonstrated that rigid PUF derived from this bio-based polyol displayed better properties compared with those of rigid PUF derived from commercially available petroleum-based polyether polyol 4110.