纳米尺度下石墨烯沥青的强韧化机制与行为特性研究

Aimed at the high-performance and durable requirement of asphalt pavement in the transportation industry, combining the front of nano-composite material science, based on the previous work and the independent patents of graphene, the research is committed to the development and research of graphene-asphalt with high-performance for pavement.Aimed at the strengthening and toughening mechanism between the interface of graphene and asphalt, the key scientific problems about the complex structure characteristics and behavioral characteristics of composites and so on are studied through micro-macro measurement and analysis methods.By fine characterization of the micro-nano scale and the spatial distribution of graphene in asphalt, the microstructure of composites including graphene and asphalt is analyzed. Combined with the physical and chemical character of graphene， regulation and optimization method of the compound-structure are explored, the synergistic working mechanism and the origin of strength and toughness of graphene and asphalt are explained.Discussed the influence rule of the rheological property of asphalt by the graphene, the characteristics of evolution of the aggregation structure and behaviour of graphene-asphalt is obtained.The composition system of composite including graphene and asphalt is preliminary formed and the preparation method of graphene-asphalt is initially explored. Changing regularity of the key behavior characteristics of the graphene-asphalt and graphene-asphalt mixture are mastered and the behavior pattern is built in order to establish the application base of high-performance graphene-asphalt for pavement. The research of the project explores and expands the functional field for nano-composite of graphene, which is expected to solve the problem of material durability for long-term service for asphalt pavement under various environments. It has important scientific significance and practical value.

瞄准交通行业高性能，耐久型沥青路面建设需求，结合纳米复合材料科学前沿，基于前期工作基础和自主石墨烯专利，开发和研究高性能路用石墨烯沥青。针对石墨烯与沥青界面的强韧化相互作用机制、采用微观、宏观测试和分析方法，展开对复合材料结构特征、行为特性等关键科学问题的研究。通过对石墨烯纳微尺度及在沥青中空间分布的精细表征，解析石墨烯沥青复合材料微观结构，结合石墨烯物理、化学特性，探索复合结构调控与优化方法，揭示石墨烯与沥青协同作用的工作机制和强韧化本源；通过探讨石墨烯对沥青流变性能的影响规律，获得石墨烯沥青聚集态结构与行为的演变特征，初步形成石墨烯沥青复合材料组成体系与制备方法，掌握石墨烯沥青及沥青混合料的关键行为特性变化规律，构建行为模式，奠定高性能路用石墨烯沥青应用基础。项目研究拓展了石墨烯纳米复合材料功能化领域，以期解决沥青路面在不同环境下长期服役的材料耐久性问题，具有重要的科学价值和应用前景。

瞄准交通行业耐久型沥青路面长期服役需要高性能路面材料支撑的发展需求，结合纳米复合材料科学前沿，采用结构特殊、性能优异的二维碳纳米材料—石墨烯（GA），开发高性能路用石墨烯沥青，展开对其结构特征、行为特性等关键问题的研究。.研究中，优化小罐球磨制备GA方法，揭示GA与沥青的作用机理，提出GA改性沥青制备工艺和材料组成，探索GA改性沥青和沥青混合料行为特征，得到如下结论和创新点：.1、证明高速剪切制备改性沥青时，导致沥青老化的主要因素是氧老化；发明通氮阻氧装置，减少老化影响效果显著。.2、采用小罐球磨工艺制备GA，提出以比表面积代替钢砂粒径级配的计算方法，获得石墨掺量、助磨剂掺量及钢砂粒径的最优制备参数；微观分析证明制备的GA品质较好，层数在5~10层。.3、提出“分子模拟技术初选-宏观分散试验筛选-紫外可见光吸收谱优选验证”的GA分散剂和基本溶剂匹配方法。比选十一种表面活性剂，获得两种表面活性剂和对应溶剂：硬脂酰胺（三氯乙烯）和聚乙烯吡咯烷酮（无水乙醇）。.4、基于均匀设计法，以测力延度、抗车辙因子、蠕变恢复率等沥青性能指标为响应值，建立模型求解，获得硬脂酰胺（EBS）GA改性沥青的最优材料组成及制备工艺。.5、借助紫外分光试验，创建基于朗伯-比尔定理的聚乙烯吡咯烷酮（PVP）GA改性沥青材料组成设计方法，通过胶束理论证明表面活性剂对GA的片层存在剥离与分散作用。.6、证明在光、热及水耦合老化作用下，GA改性沥青抗老化性能远高于基质沥青。.7、借助多种微观分析方法揭示了GA与沥青的作用机制，评价GA团聚物在沥青中的分布状态和特征；解释GA改善沥青性能的原因；认为GA与沥青间仅为物理共混作用；发现GA改性沥青的玻璃态转变温度下降，说明沥青的抗低温性能提高显著。.8、试验研究证明GA改性沥青混合料流变性能、路用性能，力学性能优异，与矿料的粘附性能良好。.研究表明，GA在沥青中的均匀分散程度是提升沥青性能的关键因素，GA的掺入使沥青改性效果显著，认为GA改性沥青性能仍存在较大提升空间。