Patent · US Expired

Star polymer viscosity index improver for oil compositions

US6034042A · kind A · utility

13Cited by
12References
18Claims
0Family size

Assignee

Inventor

Key dates

Filing dateFeb 17, 1999
Grant dateMar 7, 2000
Priority date
Expiry dateFeb 17, 2019

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC10N2040/28
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

The present invention includes star polymers which can be used as viscosity index improvers in oil compositions formulated for high performance engines. The star polymers have tetrablock copolymer arms of hydrogenated polyisoprene-polybutadiene-polyisoprene with a block of polystyrene and which provide excellent low temperature performance in lubricating oils, exhibit good thickening efficiency, and are finishable as polymer crumb.

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