| abstract |
The present invention is directed to methods of producing reduced viscosity oleaginous compositions containing Group I-B, II-A and II-B metal, particularly copper and/or zinc, salts of the product of a polyolefin having a number average molecular weight (M n ) of at least 600 which has been substituted with at least one dicarboxylic acid producing moiety per polyolefin molecule, wherein the metal salt product is contacted with lower aliphatic or cycloaliphatic amines having from 1 to 4 nitrogen atoms per molecule. The compositions of the present invention can also provide increased stability to viscosity growth, e.g. during storage of the materials prepared by the process of this invention. The resulting solutions are useful in lubricating oils as additives, e.g., as antioxidant lube oil additives. |