多尺度纳米材料对沥青流变和老化性能的影响

采用布氏旋转黏度、动态剪切流变和弯曲梁流变试验,同时结合红外光谱试验对比研究了多尺度纳米材料对不同老化状态下4种沥青——SK-70和Alfa-70基质沥青、SBR和SBS改性沥青(SBRMA, SBSMA)流变性能的影响.结果表明:4种沥青经多尺度纳米材料改性后,布氏旋转黏度、复数模量及车辙因子均得到不同程度的提高;长期热氧和光氧老化后的疲劳因子降低,即抗疲劳性能得到改善,且对SBRMA的改善最明显.相比未改性沥青,多尺度纳米材料改性后4种沥青在各种老化方式下的复数模量老化指数均降低,而且SBSMA和SBRMA这2种聚合物改性沥青老化前后的丁二烯指数差值也降低,即4种沥青的耐热氧和耐光氧老化性能同时得到有效改善,且对SBRMA的改善效果最好.多尺度纳米材料提高了2种基质沥青的低温连续等级温度,但同时在一定程度上降低了2种聚合物改性沥青的低温连续等级温度.

Influence of Multi dimensional Nanomaterials on Rheological and Aging Properties of Asphalt

Influence of multi dimensional nanomaterials on rheological properties of four asphalts (SK 70 and Alfa 70 two base asphalts and SBSMA and SBRMA two polymer modified asphalts) after different aging methods was comparatively investigated by Brookfield rotational viscosity, dynamic shear rheology, bending beam rheology tests and Fourier transform infrared spectroscopy test. The results show that, with the multi dimensional nanomaterials added in the four asphalts, the rotational viscosity, complex modulus and rutting factor before aging are enhanced to different degree; the fatigue factor after long term thermal oxidation aging and photo oxidation aging is reduced, indicating that the anti fatigue performance is improved and the improvement for SBRMA is the most significant. The modification of multi dimensional nanomaterials decreases the complex modulus aging index of four asphalts after different aging and the butadiene index difference of SBSMA or SBRMA before and after aging, manifesting that both the thermal oxidation aging and photo oxidation aging resistance of four asphalts are enhanced effectively, and the enhancement for SBRMA is the most remarkable. Multi dimensional nanomaterials enhance the low temperature continuous grading temperature of SK 70 and Alfa 70, while reduce that of SBSMA and SBRMA to some extent.