Both wheat straw and crude glycerol are low-cost renewable feedstocks which could be promising for the production of biobased polymers. In this study, biopolyols were first prepared through liquefaction of wheat straw in crude glycerol. Effects of reaction temperature, catalyst loading, reaction time, biomass loading, and fatty acid amount on the liquefaction of wheat straw were investigated and the synthesized biopolyols were characterized. With 10 % wheat straw loading and 6% sodium hydroxide as the catalyst at 240 °C for 4 h, 89 % of what straw conversion yield can be reached. The synthesized biopolyols had a hydroxyl number of 612 mg KOH/g and an acid number of 1.3 mg KOH/g. The flame retardant PU foams were then prepared from the biopolyols and isocyanate in the presence of 25 % flame retardants including dimethyl methylphosphonate (DMMP) and expandable graphite (EG). When the mass ratio of DMMP to EG was 2:1, the limiting oxygen index value of PU foams reached 26.2 %, and vertical burning tests showed that flame-retardant PU foams can pass the V-0 rating. Fire behavior results indicated that the incorporation of DMMP and EG into the biobased PU foams can effectively reduce the smoke release and improve the smoke suppression performance, and the peak heat release rate and the peak smoke production release of the flame-retardant PU foam decreased by 40.0 % and 25.0 % compared with neat PU foam, respectively. Meanwhile, the compressive strength and the thermal conductivity of the flame-retardant PU foam were 283 kPa and 0.0295 W m⁻¹ K⁻¹, respectively. These results showed that the bio-based PU foam has great potential as flame retardant insulation material. This study provides a novel method for the production of flame-retardant PU foams through liquefaction of wheat straw in crude glycerol.

小麦秸秆和粗制甘油都是低成本的可再生原料，对于生产生物基聚合物可能很有希望。在这项研究中，首先通过麦秸在粗甘油中液化制备生物多元醇。研究了反应温度，催化剂负载量，反应时间，生物量负载量和脂肪酸含量对小麦秸秆液化的影响，并表征了合成的生物多元醇。在240°C下使用10％的小麦秸秆负载量和6％的氢氧化钠作为催化剂4小时，可以达到89％的秸秆转化率。合成的生物多元醇的羟值为612mg KOH / g，酸值为1.3mg KOH / g。然后，在25％阻燃剂（包括甲基膦酸二甲酯（DMMP）和可膨胀石墨（EG））存在下，由生物多元醇和异氰酸酯制备阻燃PU泡沫。当DMMP与EG的质量比为2：1时，PU泡沫的极限氧指数值达到26.2％，垂直燃烧测试表明阻燃PU泡沫可以通过V-0等级。着火行为结果表明，将DMMP和EG掺入生物基PU泡沫中可有效减少烟气释放，提高抑烟性能，阻燃PU泡沫的峰值热释放速率和峰值烟气释放量降低。与纯聚氨酯泡沫相比，分别为40.0％和25.0％。与此同时，^-1  K ^-1。这些结果表明，生物基PU泡沫具有作为阻燃隔热材料的巨大潜力。这项研究提供了一种通过小麦秸秆在粗甘油中液化生产阻燃PU泡沫的新方法。