18513-38-7Relevant academic research and scientific papers
Improving the aging effect of bitumen and sbs modified bitumen by using newly prepared antioxidants
Mansour, Ahmed S.,Ghaly,Eldidamony, Akram M.,Nessim,Mohamed, Manal G.
, p. 2213 - 2233 (2020/09/02)
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).
MECHANISM OF AZO COUPLING. VI. REACTIONS OF THE p-NITROBENZENEDIAZONIUM ION WITH (PHENYLAZO)PHENOL AND ITS DERIVATIVES
Bagal, I. L.,Zul'figarov, O. S.,Yurchenko, V. V.,Trachevskii, V. V.,El'tsov, A. V.
, p. 762 - 767 (2007/10/02)
According to the results of elemental analysis, high-performance liquid chromatography, and NMR, UV, and IR spectroscopy the preparatively isolated products of the reactions of the p-nitrobenzenediazonium ion with p-(phenylazo)phenol and its derivatives are derivatives of 4,4-bis(p-nitrophenylazo)-2,5-cyclohexadien-1-one.The products are stable in the solid state and in neutral media.In acid and alkaline media they are split with the formation of the nitrobenzenediazonium ion and the corresponding p-(phenylazo)phenols.The product with a cyclohexadienone structure is regarded as a model of the second of the two successively formed intermediate complexes in the azo coupling.
