Hardwood residue(HR),a byproduct of paper industry,was liquefied by using polyethylene glycol 400(PEG400) and ethylene carbonate(EC) as the liquefaction solvents,and concentrated sulfuric acid as the catalyst to...Hardwood residue(HR),a byproduct of paper industry,was liquefied by using polyethylene glycol 400(PEG400) and ethylene carbonate(EC) as the liquefaction solvents,and concentrated sulfuric acid as the catalyst to produce bio-polyols(HRLP),which were used to synthesize polyurethane(PU) foams.The effects of conditions on the properties of HRLP and modified PU foams were investigated and the mechanism of biomass liquefaction was discussed.The optimum conditions of liquefaction were obtained as follows: reaction temperature of 160 °C,reaction time of 60 min,ratio of PEG400/EC of 8:2(w/w),and ratio of liquid/solid of 5:1(w/w).The characterization of HRLP modified PU foams suggested that HRLP could partially replace the petroleum polyols to synthesize PU foams.With the increase of the replacement percentage of HRLP,the apparent density and compressive strength of the foams increased firstly,and then decreased.Meanwhile,the thermal stability was improved slightly.展开更多
基金Funded by the National Natural Science Foundation of China(Nos.51503041 and 51472050)
文摘Hardwood residue(HR),a byproduct of paper industry,was liquefied by using polyethylene glycol 400(PEG400) and ethylene carbonate(EC) as the liquefaction solvents,and concentrated sulfuric acid as the catalyst to produce bio-polyols(HRLP),which were used to synthesize polyurethane(PU) foams.The effects of conditions on the properties of HRLP and modified PU foams were investigated and the mechanism of biomass liquefaction was discussed.The optimum conditions of liquefaction were obtained as follows: reaction temperature of 160 °C,reaction time of 60 min,ratio of PEG400/EC of 8:2(w/w),and ratio of liquid/solid of 5:1(w/w).The characterization of HRLP modified PU foams suggested that HRLP could partially replace the petroleum polyols to synthesize PU foams.With the increase of the replacement percentage of HRLP,the apparent density and compressive strength of the foams increased firstly,and then decreased.Meanwhile,the thermal stability was improved slightly.