| abstract |
Claimed are automotive lubricant compositions comprising a base solution and an ashless polymer dispersant. This ashless polymer dispersant has a polymer backbone consisting of 2 to 30 monomer repeating units each containing a hydrocarbon chain functionalized by the presence of at least one electronegative element or moiety. A polar tail group comprising a polar tail group bonded to a polar head group comprising a polar moiety selected from at least one of acid, ester, amide or alcohol moieties, and having a number average molecular weight of 500 to 10,000 Have This composition provides enhanced seal resistance and good oxidative stability in automotive applications compared to common commercial products. Further, the low temperature viscosity of the automotive lubricant composition using the target dispersant is superior to the composition using a general commercially available dispersant, the target dispersant does not react with ZDDP and Therefore, it does not reduce the wear resistance performance of ZDDP. |