SEBS/SBR复合改性沥青性能分析

Performance Analysis of SEBS/SBR Composite Modified Asphalt

为探究氢化苯乙烯-丁二烯嵌段共聚物/丁苯橡胶(SEBS/SBR)复合改性沥青的综合性能,采用高速剪切机制备SBR改性沥青、SEBS改性沥青及不同SEBS掺量的SEBS/SBR复合改性沥青,通过常规性能试验、动态剪切流变试验(DSR)、低温弯曲梁流变试验(BBR)及旋转薄膜加热试验(RTFOT)分析其高低温性能及抗老化性能;利用傅里叶红外光谱仪(FTIR)研究SEBS/SBR复合改性沥青的改性机理。研究结果表明,SEBS/SBR复合改性沥青的软化点最大增幅为23.4%,沥青的高温性能提升;5℃时的延度最大增加了约20倍,沥青的低温性能显著提升;老化后的软化点差从6.2℃降低至1.5℃,残留针入度比从71.6%增大至79.1%,抗老化性能显著提升;SEBS和SBR改性剂与基质沥青之间仅发生了物理作用,并未发生化学反应,因此,SEBS和SBR对基质沥青的改性属于物理共混。

In order to explore the comprehensive performance of SEBS/SBR composite modified asphalt,SBR modified asphalt,SEBS modified asphalt and SEBS/SBR composite modified asphalt with different SEBS content were prepared by high⁃speed shear mechanism.The high and low temperature performance and anti⁃aging properties were evaluated by conventional performance test,dynamic shear rheology test(DSR),low temperature bending beam rheological test(BBR)and rotating thin film oven test(RTFOT).Fourier transform infrared spectroscopy(FTIR)was used to evaluate the performance of the composite modified asphalt.The modified mechanism of SEBS/SBR composite modified asphalt was explored by FTIR.The research results showed that the maximum increase in softening point of SEBS/SBR composite modified asphalt was 23.4%,and the high⁃temperature performance of asphalt was improved;The maximum increase in ductility at 5℃was nearly 20 times,and the low⁃temperature performance of asphalt was significantly improved;After aging,the softening point difference decreased from 6.2℃to 1.5℃,and the residual penetration ratio increased from 71.6%to 79.1%,which significantly improved the anti⁃aging performance;There was only physical interaction between SEBS and SBR modifier and base asphalt,but no chemical reaction occurred.The modified type of SEBS and SBR on base asphalt was physical blending.