【摘要】 将聚氨酯（PU）作为沥青改性剂可有效提升沥青的性能，延长沥青路面的服役寿命。文中介绍了PU的分子结构和应用场景，综述了PU改性沥青的制备工艺及改性机理研究进展。PU改性沥青制备过程中改性剂投料顺序以及制备参数的选取均会影响改性沥青的技术性能。PU改性沥青的机理兼具化学与物理改性，PU可以与沥青发生化学反应生成新键，同时PU分子链通过交联形成三维网状结构，二者协同提高沥青的性能。更多还原

【Abstract】 Polyurethane(PU) can be used as a modifier for asphalt to effectively enhance the performance of asphalt and prolong the service life of asphalt pavement. In this paper, the molecular structure and application scenarios of PU were introduced and the research progress of the preparation process and the mechanism of PU modified asphalt were reviewed. The selection of the modifier feeding sequence and the preparation parameters in the preparation process of PU-modified asphalt both affected the technical performance of the modified asphalt. The mechanism of PU-modified asphalt involved both chemical and physical modification. PU could chemically react with asphalt to form new bonds, while the PU molecular chains crosslinked to form a three-dimensional network structure. The two mechanisms worked together to improve the performance of asphalt.更多还原