SYNTHETIC ESTER LUBRICANT STABILIZER COMPOSITION

摘要

An antioxidant stabilizer composition is disclosed that is the reaction product of a diphenylamine and an N-aryl naphthylamine in the presence of an organic peroxide. The mole ratio of diphenylamine: N-aryl naphthylamine is from 1:1 to 10:1. This results in more oligomeric reaction products and significantly less unreacted monomeric residual reactants. The resultant product composition comprises diphenylamine homooligomers and diphenylamine/N-aryl naphthylamine cross oligomers. The diphenylamine and N-aryl naphthylamine are desirably substituted with alkyl groups having from 1 to 20 carbon atoms or styryl groups. The reaction temperature is preferably from about 130.degree. to 150.degree.C. The controlled reaction conditions allow the use of solvents with extractable hydrogen atoms without producing significant amounts of dehydrocondensation between the solvent and the diamines. The reaction products have superior oxidative resistance in the Oxidation Corrosion Stability Test (OCS) and Vapor Phase Coker Test over products products produced under other conditions.