Improving the aging effect of bitumen and sbs modified bitumen by using newly prepared antioxidants

Abstract

Thermal oxidative aging of bitumen has a bad effect on the durability of bitumen binder. We aim in this research to reduce the thermal oxidative aging of bitumen by preparing two compounds namely (R-OCH3=AO1) and (R-NO2=AO2) and examined as antioxidants. These compounds characterized via the conventional spectral tools of analysis (FTIR and 1H-NMR). They mixed with local bitumen (60/70) separately at different concentrations ratios (0.25, 0.5 and 1%) then aged via TFOT at 170°C for 5 hours. The effect of them evaluated based on the changes in FTIR, total acid number (TAN) and the physical properties of bitumen before and after the thermal oxidation. The results showed that 0.5, 1% of AO1 antioxidant gave the best results of modification of bitumen. After the samples modified with these two concentration ratios of antioxidant AO1, they mixed with 3% Styrene Butadiene Styrene (SBS) polymer then aged via TFOT at 170 C for 5 hours. The effect of the antioxidant in reducing the aging of the SBS modified bitumen (SBSMB) was evaluated through the changes in FTIR, TAN and the physical properties of bitumen before and after the thermal oxidation. The results illustrated that the best modification of SBSMB was at 1% (AO1).