In this study, microalgae biodiesel (MB) was prepared by chemically modifying microalgae acidified oil, which was in turn added as a modifier to a pre-synthesized crumb rubber-styrene-butadiene-styrene (CR/SBS) modified asphalt to prepare MBCR/SBS composite modified asphalt. Rotational viscosity measurement showed that viscosity of MBCR/SBS-2 asphalt meets the requirements of Superpave specifications. Dynamic shear rheometer and multiple stress creep recovery tests revealed that MBCR/SBS-2 asphalt exhibited the largest complex modulus (G^∗), smallest phase angle (δ) in high frequency range, and higher average recovery rate (R) after rotating thin film oven test. The fatigue cracking analysis revealed that higher content of MB results in better resistance to fatigue cracking under intermediate temperature. Separation analysis showed that MBCR/SBS-2 asphalt possessed softening point difference of 2.9 °C. Fourier transform infrared spectroscopy and proton nuclear magnetic resonance spectroscopy analyses confirmed more unsaturated groups in the MB than in the base asphalt, and amide groups bonded to the free radicals of CR which promoted the development of network structure resulting in enhanced mechanical properties of MBCR/SBS modified asphalt than pristine CR/SBS asphalt. In addition, a proposed synthesis and performance mechanism of MBCR/SBS asphalt was elaborated. This study based on simplified preparation and enhanced performance of MBCR/SBS asphalt composite modified asphalt, could be of potential interest for practical applications in construction and highway industries.

在这项研究中，通过对微藻酸化油进行化学改性来制备微藻生物柴油（MB），然后将其作为改性剂添加到预先合成的碎屑橡胶-苯乙烯-丁二烯-苯乙烯（CR / SBS）改性沥青中，从而制备MBCR / SBS复合改性沥青。旋转粘度测量表明，MBCR / SBS-2沥青的粘度符合Superpave规范的要求。动态剪切流变仪和多次应力蠕变恢复测试表明，MBCR / SBS-2沥青表现出最大的复数模量（G ^∗），高频范围内的最小相角（δ）和旋转薄膜烤箱测试后的较高平均回收率（R）。疲劳裂纹分析表明，较高的MB含量导致在中等温度下具有更好的抗疲劳裂纹性。分离分析表明，MBCR / SBS-2沥青的软化点差为2.9°C。傅里叶变换红外光谱和质子核磁共振光谱分析证实，MB中的不饱和基团比基础沥青中的不饱和基团更多，酰胺基团与CR的自由基键合，促进了网络结构的发展，从而提高了MBCR / SBS的机械性能。改性沥青要比原始CR / SBS沥青好。此外，还详细阐述了MBCR / SBS沥青的合成及性能机理。