SYNTHETIC ESTER LUBRICANT STABILIZER COMPOSITION

摘要

An antioxidant stabilizer composition is disclosed that is the reaction prod uct of a diphenylamine and an N-aryl naphthylamine in the presence of an organic peroxide. The mole ratio of diphenylamine: N-ary l naphthylamine is from 1:1 to 10:1. This results in mo re oligomeric reaction products and significantly less unreacted monomeric resi dual reactants. The resultant product composition compr ises diphenylamine homooligomers and diphenylamine/N-aryl naphthylamine cross oli gomers. 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 preferab ly from about 130.degree. to 150.degree.C. The controlled reaction conditions allow the use of solvents with extractable hydrogen atoms wit hout producing significant amounts of dehydrocondensation between the solvent and the diami nes. The reaction products have superior oxidative resi stance in the Oxidation Corrosion Stability Test (OCS) and Vapor Phase Coker Test o ver products products produced under other conditions.