Dispersants and lubricating oil compositions containing same

摘要

A boron-containing dispersant composition containing one or more dispersants that are the reaction product of a polyalkenyl-substituted mono- or dicarboxylic acid, anhydride or ester; and a polyamine, in which at least one of the dispersants has a polyalkenyl moiety with a number average molecular weight of at least about 1800, and from greater than about 1.3 to about 1.7 mono- or di-carboxylic acid producing moieties per polyalkenyl moiety; and in which a ratio of wt.% of boron to wt.% of nitrogen (B/N) for the dispersant composition is from about 0.05 to about 0.24.