生物重油-胶粉界面嫁接活化机理及其改性沥青性能表征研究

橡胶沥青可显著改善沥青路面使用性能，但橡胶沥青也存在黏度高、易离析及储存稳定性差等不足。本研究利用生物重油和沥青元素相似且极性组分含量高的特点，通过胶粉与生物重油预混处理而将生物重油中极性成分嫁接到胶粉表面而活化胶粉并提高胶粉与沥青相容性，从而有效利用胶粉与生物重油的优点并克服各自缺陷。首先，基于物化手段筛选极性成分含量高的生物重油并多尺度表征生物重油与胶粉。其次，基于聚合物溶解理论与菲克扩散定律，分析生物重油中轻质组分在胶粉中的溶解变化规律及扩散效应，揭示溶胀胶粉对橡胶沥青的降黏机制。然后，借鉴密度泛函数理论及微纳观测试方法，从反应能量分布及官能团迁移角度定量阐明生物重油-胶粉界面嫁接活化机理。再次，基于聚合物共混物的热力学相容性评价理论与方法，探明生物重油预处理活化胶粉与沥青的相容性行为。最后，对生物重油活化胶粉改性沥青的性能进行协同设计与优化，实现橡胶沥青性能的全面提升。

Crumb rubber can improve the performance of asphalt pavement, but it also has the drawbacks like high viscosity, easy segregation and poor storage stability. Since heavy bio-oil, with high amount of polar components, has similar elemental composition as petroleum asphalt, it was used in this study to pretreat the crumb rubber. During the treatment process, heavy bio-oil first caused the crumb rubber to swell and then its polar components were grafted onto the exterior surfaces of crumb rubber particles, which will increase the compatibility between rubber particles and asphalt. This approach can utilize the advantages of both crumb rubber and heavy bio-oil while minimizing their disadvantages. Firstly, heavy bio-oils with high amount of polar components were selected through physicochemical approaches and heavy bio-oil and crumb rubber were characterized on multiple scales. Meanwhile, based on polymer dissolution theory and Fick's law, the solubility and diffusion of light weight component of heavy bio-oil within crumb rubber particles were evaluated, which can help to explain the mechanism of lower viscosity for binders produced with swollen rubber. By using density functional theory and micro-testing methods, the grafting mechanism of polar molecules from heavy bio-oil onto the exterior surface of rubber particles was then investigated based on reaction energy distribution and functional group migration. In addition, the compatibility between activated rubber and asphalt was evaluated using compatibility evaluation method for polymers. Finally, the performance of heavy bio-oil activated rubber asphalt was optimized to improve the overall performance of crumb rubber modified asphalt.