摘要 |
An antioxidant composition comprising at least one diaromatic amine compound of the formula <CHEM> wherein R, Ra and Rc are independently selected from the group consisting of hydrogen and <CHEM> A is alkyl of 1-12 carbon atoms, haloalkyl, aralkyl, mercapto or alkylmercapto; X is alkyl of 1-12 carbon atoms; and n is 0 or 1 with the priviso that where R, Ra and Rb are <CHEM> ; n is 0, or that where only R is <CHEM> n is 1; and at least one substituted melamine compound of the formula <CHEM> wherein Rc through Rh are independently selected from the group consisting of hydrogen, alkyl, substituted alkyl, cycloalkyl, aryl and substituted aryl. The relative weight ratio of formula I to formula II compounds in the composition of this invention can range from about 1:10 to about 10:1. The above compositions are highly effective stabilizers for synthetic lubricants. |