Patent · US Expired

Asymmetric triblock copolymer viscosity index improver for oil compositions

US5458792A · kind A · utility

6Cited by
6References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 11, 1994
Grant dateOct 17, 1995
Priority date
Expiry dateAug 11, 2014

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC08L53/025
  • WIPO fieldMacromolecular chemistry, polymers
  • WIPO sectorChemistry

Abstract

The present invention includes asymmetric triblock copolymers which are used as viscosity index improvers in oil compositions formulated for high performance engines. The triblock copolymers have the block structure hydrogenated polyisoprene-polystyrene-hydrogenated polyisoprene wherein the ratio of the number average molecular weights of the first and second hydrogenated polyisoprene blocks is at least 4.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.