Mixed phenol/dimercaptothiadiazole-derived hydroxythioether borates as antioxidant/antiwear multifunctional additives

A lubricant composition comprising a major poropration of a lubricating oil or grease prepared therefrom and an effective multifunctional amount of a product of reaction made by reacting in any convenient reaction sequence or (1) dimercaptothiadiazole of the formula:

• ##STR6## with (2) an alkylene oxide of the formula:
• ##STR7## where R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are each independently H, or C.sub.1 to about C.sub.60 hydrocarbyl and can optionally contain S, N, and/or O, and (3) a phenolic compound, (4) a suitable boronating agent in substantially equimolar, less than molar or more than molar amounts and where reaction temperatures vary from about 50.degree. to about 300.degree. C. and said reaction times vary from about 0.5 to about 10 hours.

A process of making a product suitable for use as a lubricant additive comprising reacting in any convenience reaction sequence or (1) dimercaptothiadiazole of the formula:

• ##STR8## with (2) an alkylene oxide of the formula:
• ##STR9## where R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are each independently H, or C.sub.1 to about C.sub.60 hydrocarbyl and can optionally contain S, N, and/or O, (3) a phenolic compound, and (4) a suitable boronating agent in substantially equimolar, less than molar or more than molar amounts, said reaction temperatures varying from about 50.degree. to about 300.degree. C. and said reaction times varying from about 0.5 to about 10 hours.