摘要 |
A lubricating composition comprises a base oil and between 10 ppm and 1000 ppm by mass of a viscosity modifier, the viscosity modifier comprising a polymer having a number average molecular weight greater than 500,000. The polymer's side-chains may be branched or unbranched. The polymer is preferably selected from the group consisting of polyolefin, poly alpha olefin, poly internal olefin, ethylene-propylene copolymers, ethylene-propylene-diene copolymers, ethylene-propylene-acrylate copolymers, ethylene-propylene-methacrylate copolymers, ethylene-propylene-aromatic copolymers, ethylene-propylene-diene-acrylate copolymers, ethylene-propylene-diene-methacrylate copolymers, and combinations thereof.
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