| 摘要 |
A lubricant composition comprising a major amount of baseoil lubricant and a minor amount of lubricant additive. The lubricant additive includes (a) a dispersant containing at least one member selected from hydrocarbyl-substituted succinimides, hydrocarbyl-substituted amines, and Mannich base adducts derived from hydrocarbyl-substituted phenols condensed with an aldehyde and an amine, and (b) a viscosity index improver that includes a substantially linear block copolymer having a number average molecular weight as determined by gel permeation chromatography ranging from about 50,000 to about 250,000. The block copolymer is derived from a conjugated diene monomer containing no less than 5 carbon atoms and a monoalkenylarene monomer, wherein the block copolymer has an aromatic content ranging from about 10 wt.% to about 50 wt.% and an olefinic unsaturation ranging from about 0.5 wt.% to about 5 wt.%. |
