Sasobit/SBR复合改性沥青流变性能研究

Study on the Rheological Properties of Sasobit/SBR Composite Modified Asphalt

为了得到一种兼顾高低温性能且环境友好的复合改性沥青,研究选用Sasobit与SBR两种材料作为改性剂,制备得到一种高低温性能兼顾的复合改性沥青。通过对不同掺配比例(Sasobit掺量为0%、1%、2%、3%、4%;SBR掺量为0%、3%、4%、5%、6%)复合改性沥青老化前后的流变性能进行研究,确定了Sasobit/SBR复合改性沥青的最佳掺配比例,利用红外光谱实验研究复合改性沥青的改性机理,并利用荧光显微镜观察改性剂在沥青中的分散情况。研究结果表明:Sasobit的加入会提高沥青的高温流变性能,降低沥青的低温性能;SBR的加入会提高沥青的低温流变性能,对高温流变性能的提升不明显。在兼顾经济性的情况下,复合改性沥青的最佳掺配比例为3%Sasobit+5%SBR。红外光谱分析表明,复合改性沥青的改性机理为物理改性,两种改性剂在沥青中分布均匀,有交联结构产生。

To develop a composite modified asphalt that balances high and low-temperature performance while being environmentally friendly,this study selected Sasobit and SBR as modifiers to prepare a composite modified asphalt with good high and low-temperature properties.The rheological properties of the composite modified asphalt before and after aging with different mixing ratios(Sasobit content of 0%,1%,2%,3%,4%;SBR content of 0%,3%,4%,5%,6%)were studied to determine the optimal mixing ratio of Sasobit/SBR composite modified asphalt.The modification mechanism of composite modified asphalt was investigated using infrared spectroscopy,and the dispersion of modifiers in asphalt was observed using fluorescence microscopy.The results show that the addition of Sasobit improves the high-temperature rheological performance of asphalt and reduces its lowtemperature rheological performance;the addition of SBR improves the low-temperature rheological performance of asphalt but has no significant effect on high-temperature rheological performance.Considering cost-effectiveness,the optimal mixing ratio for the composite modified asphalt is 3%Sasobit+5%SBR.The study of the modification mechanism using infrared spectroscopy indicates that the modification mechanism of composite modified asphalt is physical modification,with both modifiers evenly distributed in the asphalt and cross-linking structures formed.