Rapid Liquefaction of Wood in Polyhydric Alcohols Under Microwave Heating and its Liquefied Products for Preparation of Rigid Polyurethane Foam

Comparing to the conventional bath heating, the effects of liquefaction parameters on the degree of liquefaction of wood in polyhydric alcohols by using microwave as an energy source were evaluated. Polyurethane foams were successfully prepared from the liquefied biomass-based polyols. The effects of heating methods (conventional bath heating and microwave) and liquefaction reaction time on the properties of liquefied biomass-based polyols were investigated. The influences of isocyanate index on the properties of rigid polyurethane foams were also discussed, and feasible formulations for preparing liquefied biomass-based polyurethane foams were proposed. The results indicated that rapid liquefaction of wood in polyhydric alcohols under microwave heating could be achieved. The foams prepared from liquefied biomass-based polyols obtained by microwave-assistant liquefaction exhibited excellent mechanical properties.