Fossil fuel resources depletion and growing concern about environmental issues have raised the demand for newly sustainable biomaterials. To address this challenge, a new type of biodegradable and environmental rigid polyurethane foam called rigid polyurethane foams (RPUF)-M from full modified soy-based polyols have been synthesized without the addition of petroleum-based polyols. On the basis of the analysis of structure-activity relationship, a new kind of biobased polyurethane polyols called Bio-polyol-M was designed and synthesized directly from epoxidized soybean oil and a novel polyhydroxy compound in a three-step continuous microflow system. In the continuous microflow system, the epoxidation of soybean oil, the synthesis of GLPO (glycerine with styrene oxide), and the ring-opening reaction of epoxidized soybean oil were coupled. Another soy-polyol called Bio-polyol-B was synthesized in batch mode. In comparison to those of Bio-polyol-B, Bio-polyol-M had a higher hydroxyl number and a much lower viscosity. The RPUF-M also possessed a series of advantages over the rigid polyurethane foam called RPUF-B from Bio-polyol-B.
Keywords: microflow system; rigid polyurethane foam; soy-polyol.