Investigation on different approaches for detecting polymer content in styrene-butadiene-styrene modified asphalt

Abstract This paper investigates three approaches for detecting the content of styrene-butadiene-styrene (SBS) in its modified asphalt. The physical, rheological, and structural analysis are respectively conducted by the conventional tests, dynamic shear rheology, and Fourier transform infrared spectroscopy (FTIR) tests. The results show that the fitting coefficient of the quadratic equation between the SBS content and viscosity or softening point or phase angle is very high, but these tests are time-consuming. The absorption peak at 966 cm -1 (the absorption peak area of 966 cm -1 is marked as A966, the same below) is selected as the characteristic peak of SBS, and the absorption peaks of 1377 cm -1 , 811 cm -1 and 749 cm -1 are selected as the characteristic peak of the base asphalt in SBS modified asphalt. Comparing the applicability, accuracy and sensitivity of A 966 /A 1377 , A 966 /A 811 , and A 966 /A 749 , it is found that A 966 /A 811 is more suitable as the indicator to determine the content of SBS. FTIR can realize the rapid and accurate detection of SBS content. Furthermore, A 966 /A 811 has a good quadratic relationship with the performance of the modified asphalt.