目的 为了提高精制木质素的提取率，改善聚氨酯发泡材料的力学性能，增强木质素的利用率，降低聚氨酯发泡材料的生产成本，扩大使用范围。方法 通过碱溶酸析、液-液提取及超滤膜过滤处理工艺获取精制木质素，采用预聚体法合成精致木质素基聚氨酯发泡材料。结果 当NaOH溶液浓度为2.5 mol/L时，提取率最高;H2SO4浓度对提取率无明显影响;精制木质素的添加增大了泡沫密度，提高了压缩强度和拉伸强度。结论 当精制木质素质量分数为10%、二月桂酸二丁基锡质量为0.24 g、三乙醇胺质量为0.04 g时，制备的精制木质素基聚氨酯发泡材料的性能相对最优。

Refined lignin is prepared from industrial alkali lignin obtained from papermaking black liquor, the influence of NaOH solution concentration and H2SO4 concentration on the extraction rate of refined lignin is explored, and the foam density and compressive strength of refined lignin-based polyurethane foam materials are explored. Tensile strength improves the extraction rate of refined lignin, refined lignin improves the mechanical properties of polyurethane foam materials, enhances the utilization rate of lignin, reduces the production cost of polyurethane foam materials, and expands the scope of use. Refined lignin is obtained through alkali-dissolving acid precipitation, liquid-liquid extraction and ultrafiltration membrane filtration treatment process, and the refined lignin-based polyurethane foam material is synthesized by the prepolymer method. When the concentration of NaOH solution is 2.5 mol/L, the extraction rate is the highest; the concentration of H2SO4 has no obvious effect on the extraction rate; the addition of refined lignin increases the foam density and improves the compressive and tensile strength. When the mass fraction of refined lignin is 10%, the mass of dibutyltin dilaurate is 0.24 g, and the mass of triethanolamine is 0.04 g, the performance of the refined lignin-based polyurethane foam material is optimal.