Amine-coupled hindered phenols and phosphites as multifunctional antioxidant/antiwear additives

#1. Field of the Invention

#This application is directed to amine coupled hindered phenol and phosphite derivatives useful as multifunctional antioxidant/antiwear lubricant additives and to lubricant compositions comprised thereof.

#2. Description of Related Art

#Approximately 62.0 g (0.3 mole) of 2,6-di-tert-butylphenol, 25.0 g (0.308 mole) of paraformaldehyde, 9.0 (0.15 mole) of ethylenediamine, and 150 ml of hexane were added into a suitably equipped 500 ml four-necked flask. This reaction mixture was then heated to the boiling temperature of hexane and was refluxed over a course of three hours, and the water which formed was collected in a Dean-Stark trap. Then it was cooled to ambient temperature and reacted with 91.9 g (0.3 mole) of bis(2-ethylhexyl) phosphite and 25.0 g 0.308 mole) of paraformaldehyde. Again, it was heated to the boiling temperature of hexane and was refluxed for three hours while azeotropically removing water. Finally, the reactants were heated at 110.degree. C. to remove all the volatiles via distillation to produce approximately 179.3 g of a viscous material.

#The amine coupled phosphite-phenol product was blended into mineral oils and evaluated for antioxidant performance using the Catalytic Oxidation Test at 325.degree. F. for 40 hours, and the Catalytic Oxidation Test at 325.degree. F. for 72 hours (Table 1).

#The Catalytic Oxidation Test consists basically of bubbling a stream of air through a volume of the lubricant at the rate of five liters per hour respectively at 325.degree. F. for 40 hours and 72 hours. See U.S. Pat. No. 3,682,980 incorporated herein by reference for further details.