微纳米SiO2改性沥青的制备及性能评价

Preparation and performance assessment of micro-nano-SiO2 modified asphalt

摘要:

随着道路交通量和车辆荷载的增加，对高温地区高速公路的沥青质量提出了更高的要求。为了制备高性能的改性沥青，以胺基修饰微纳米SiO2（10 μm和20 nm粒径）对基质沥青进行化学改性。首先以偶氮二异丁腈为引发剂，使用马来酸酐对基质沥青进行化学改性制备活化沥青（MQL），再利用接枝了聚乙烯亚胺的SiO2（PEI-SiO2）进行熔融共混改性得到改性沥青（PEI-SiO2-MQL）。采用SEM表征沥青的表面形貌。结果表明，相比于纯SiO2物理改性沥青，PEI-SiO2在沥青中分散性更佳。FTIR分析表明，PEI-SiO2与沥青之间不仅有化学作用还有物理作用。软化点、流变和老化实验结果表明，PEI-SiO2-MQL的高温稳定性、抗车辙和抗老化性能均得到改善。经胺基修饰的微纳米SiO2改性沥青在高温地区高速公路方面有很大的应用潜力。

Abstract:

With the increase in traffic volume and vehicle load, higher demands are put forward on the quality of expressway in high-temperature areas. In order to prepare high-performance modified asphalt, the base asphalt is chemically modified with amine-functionalized micro-nano-SiO2 (d=10 μm and 20 nm). Using azobisisobutyronitrile as an initiator, Maleic anhydride (MAH) reacted with base asphalt to form activated asphalt (MQL). Then the modified asphalt (PEI-SiO2-MQL) was obtained by polyethyleneimine-modified SiO2 (PEI-SiO2) and MQL under melt blending condition. The surface morphology of the asphalt characterized by SEM reveals better dispersion of PEI-SiO2 in asphalt in comparison to that in pure SiO2. The FTIR analysis shows that there are both chemical reactions and physical interactions between PEI-SiO2 and asphalt. The results of softening point, rheology and aging tests demonstrate improvements in high-temperature stability, anti-rutting and anti-aging performance of PEI-SiO2-MQL. Asphalt with amine surface-modified micro-nano-SiO2 modification has great potential as road materials on expressway in high-temperature areas.