Rheological Properties of Derivative Fractions Composed of Aromatics, Resins, and Asphaltenes

摘要

The chemical composition of the asphalt binder determines its rheological and mechanical properties. The objective of this study is to reveal the rheological properties of derivative fractions composed of aromatics, resins, and asphaltenes. First, asphalt binder (pen grade 60/80) was separated into four fractions, and then resins and asphaltenes were doped into aromatics at various contents to fabricate four derivative fractions named AR1, AR2, AA(s)1, and AA(s)2. The frequency-temperature sweep was conducted by a dynamic shear rheometer (30 similar to 80 degrees C, 0.01 similar to 20 Hz, and 0.01 % shear strain). The test results showed that with the increase of resins or asphaltenes content, the complex shear modulus increased, the phase angle value reduced, and the glass transition temperature increased, indicating that an increase in polarity led to higher stiffness and elasticity. The separated and derivative fractions in this study have been proved as thermo-rheologically simple materials due to their smooth Black diagram curves and master curves. Saturates with simple aliphatic chains had a constant phase angle value regardless of temperature and frequency. Aromatics, resins, and derivative fractions had a similar Black diagram and master curve shape characterized by a plateau region in the phase angle values. Moreover, the reduced frequency at phase angle plateau shifted from high to low frequency when the asphaltenes content increased.