| abstract |
A polymeric lubricating oil additive containing pendant perfluoroaliphatic urethane units that behaves as a Viscosity Index Improver and a fuel economy enhancer when added to lubricating oil compositions. The polymeric substrate may be a copolymer of 15-85 mole % ethylene and propylene or a terpolymer of 15-85 mole % ethylene, propylene, and 20-80 mole% of a non-conjugated diene or triene (C₃-C₁₀) alpha olefin. The copolymer or terpolymer substrate has a molecular weight range of about 5,000 to about 500,000. A graft copolymer or terpolymer containing pendant isocyanate groups is prepared by reacting the ethylene propylene co- or terpolymer with an acrylating agent. Post-reacting the copolymer or terpolymer containing the pendant isocyanate group with a perfluoroaliphatic alcohol generates the additive. |