Abstract: Aromatic amine oligomer antioxidants for lubricating oil were prepared by formaldehyde condensation method, the effects of different catalytic conditions on the structure and properties of the products were investigated, and triethylamine was selected as the catalyst. The results indicated that the formaldehyde condensation reaction of N-octylphenyl-1-naphthylamine under alkaline catalysis mainly occurs on the aromatic ring, and the product had good antioxidant performance for lubricating oil. The optimum synthesis conditions were as follows: triethylamine as catalyst, a reaction temperature of 65 ℃, a molar ratio of N-octylphenyl-1-naphthylamine to polyformaldehyde of 1:0.75, and a reaction time of 40 h.

Key words: aromatic amine oligomer, antioxidant, formaldehyde condensation