| 摘要 |
Oil compositions comprising a lubricating oil and oil-soluble ethylene-alpha-olefin copolymer viscosity index improvers are substantially haze-free when said compositions contain an anti-hazing effective amount of a hydrocarbyl substituted succinic acid. The ethylene-alpha-olefin copolymer comprises intramolecularly heterogeneous and intermolecularly homogeneous copolymer chains containing at least one crystallizable segment of methylene units and at least one low crystallinity ethylene-alpha-olefin copolymer segment, wherein said at least one crystallizable segment comprises at least about 10 weight percent of said copolymer chain and contains at least about 57 weight percent ethylene, wherein said low crystallinity segment contains not greater than about 53 weight percent ethylene, and wherein said copolymer has a molecular weight distribution characterized by at least one of a ratio of Mw/Mn of less than 2 and a ratio of Mz/Mw of less than 1.8, and wherein at least two portions of an individual intramolecularly heterogeneous chain, each portion comprising at least 5 weight percent of said chain, differ in composition from one another by at least 7 weight percent ethylene. The invention also relates to the process for preparing said compositions. |
