Preparation And Application Of Bio-polyol Phosphonate In Polyurethanc Foams

Three heteropolyacids, i.e., H3PW12O40, H4SiW12O40and H6P2W18O62, were synthesizedand used as the catalysts for bagasse liquefaction. The effects of the liquefaction conditions onresidue yield, which demonstrated the efficiency of the liquefaction, were investigated.H3PW12O40and H4SiW12O40presented higher catalytic efficiency than H6P2W18O62under thesame conditions. The reaction temperature, the reaction time and the catalyst dosage hadsignificant impacts on the residue yield. The residue yield was2.5%under the followingconditions: temperature160°C, reaction time120min and catalyst dosage4%. Theliquefaction behavior of lignocellulose with the catalyst of silicontungtic acid was also studied.The result showed that lignin and hemicelluloses degraded more easily than cellulose;Cellulose in amorphous region degraded more easily than that in crystalline region did.H3PW12O40and H4SiW12O40were supported on porous silica gel by adsorption andimpregnation, respectively. The results showed that silicontungstic acid supported on silicawas a strong, thermal stable solid acid with large surface area, suggesting that the supportedacid was a suitable catalyst for liquefaction. The residue yield was reduced from5.4%to2.0%when the acid loadings increased from10%to57%. The calcination temperature had aneffect on acid strength. The silicontungstic acid presented high acid strength when thecalcination temperature was200°C. The hydroxyl number varied in the range between290and370mg KOH·g-1, indicading that this kind of liquefaction product can be used as thepolyol components in the manufacture of rigid polyurethane foams.A bio-polyol phosphonate, which acted as the polyol component in the preparation ofpolyurethane foam, was synthesized from halogenated bio-polyol and trimethylphosphite viathe Michaelis-Arbuzov rearrangement. The FT-IR spectra showed that thephosphorus-containing group was introduced into the polyol chain. The viscosity varied in therange between448and553mPa·s and hydroxyl number ranged from243to231mg KOH/g,suggesting that the bio-polyol phosphonate was a suitable polyol component for preparationthe polyurethane foam. The value of limiting oxygen index of polyurethane foam containingbio-polyol phosphonate was in the range of24to28, while that of polyurethane foam withoutbio-polyol phosphonate was23, demonstrating the improvement of the flame retardancy bythe introduction of the phosphorus-containing group into the polymer. The initialdecomposition temperature decreased from240°C to215°C, which favored to improve thefire-retardant properties of polyurethane.