Patent · US Expired

Viscosity index improvers for lubricating oil compositions

US7163913B2 · kind B2 · utility

7Cited by
16References
14Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 1, 2003
Grant dateJan 16, 2007
Priority date
Expiry dateMar 23, 2025

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC10N2040/25
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

A polymer suitable for use as a viscosity index improver for lubricating oil compositions, which is at least one, at least partially hydrogenated linear or star-shaped random copolymer of isoprene and butadiene, in which at least 70 wt. % of the butadiene is incorporated into the polymer as 1,4 units and the weight ratio of isoprene addition product to butadiene addition product in the copolymer is in a range of from about 90:10 to about 70:30.

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