Acetic acid lignin(AAL) was isolated from acetic acid pulping waste liquor. The structure of acetic acid lignin was characterized by Fourier infrared spectroscopy ( FTIR) and P-NMR spectrum. And the molecular mass distribution of acetic acid lignin was determined on a gel permeation chromatography ( CPC). Rigid polyurethane foams were prepared from acetic acid lignin, polyether polyol and toluene diisocyanate in the presence of catalyst, silicone surfactant and foaming agent. Thermal stability and physical characteristics of AAL-based polyurethane foams were determined by TGA /DSC and compression tests, respectively. And the cell structure of AAL-based PUF was observed by scanning electron microscopy ( SEM ). The results showed that the acetic acid lignin contained highly reactive hydroxyl groups as reactive chemical reaction sites and can be used to replace part of polyols in the synthesis of polyurethane foams. The polyurethane foam presented better compressive strength. When AAL content was 5% , the compression strength was 1. 325 Mpa,which was higher 63% than pure PU foams. And the compression modulus reached the maximum, which was 0. 181 Mpa. The most rapid degradation temperature of AAL-based polyurethane foam decreased with AAL contents increasing. The glass transition temperature had no distinct change . The SEM images suggested that the polyurethane foam containing acetic acid lignin had smooth surface and homogeneous foam structure.%将乙酸制浆法废液中的木质素进行提取和精制,采用红外光谱(FTIR)、31P-NMR谱和凝胶渗透色谱(GPC)对其结构进行表征,并利用乙酸木质素、聚醚多元醇和甲苯二异氰酸酯在发泡剂和催化剂的条件下合成聚氨酯硬泡.采用TG、DSC和压缩测试对聚氨酯硬泡的热学和力学性能进行研究,并用扫描电子显微镜观察聚氨酯硬泡的泡孔结构.结果表明:乙酸木质素作为多羟基聚合物,可以部分代替聚醚多元醇和异氰酸酯发生反应制备聚氨酯材料；当乙酸木质素添加量为5%时,聚氨酯硬泡的压缩强度达到1.325 MPa,比未添加木质素的泡沫高出约63%,此时的压缩模量也达到0.181 MPa；随着乙酸木质素添加量增加,乙酸木质素基聚氨酯硬泡的最快分解温度下降,而玻璃化转变温度没有明显升高；乙酸木质素基聚氨酯硬泡泡孔平整均匀.
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