Environmentally friendly viscosity index improving compositions

摘要

A lubricant composition having improved viscosity index characteristics is described that comprises (A) at least one vegetable or synthetic triglyceride oil of the formula <IMAGE> wherein R1, R2 and R3 are aliphatic hydrocarbyl groups having at least 60 percent monounsaturated character and containing from about 6 to about 24 carbon atoms and further wherein an oleic acid moiety:linoleic acid moiety is from about 2 up to about 90 and (B) at least one mixed ester of a carboxy-containing interpolymer. Optionally, the composition may also contain (C) a synthetic ester base oil, and (D) an antioxidant.