Sternpolymer Viskosetätsindexverbesserung für Schmierölzusammensetzungen

摘要

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 triblock copolymer arms of hydrogenated polyisoprene and polystyrene wherein the polystyrene is placed near the core of the star polymer to provide excellent low temperature performance and finishability as a polymer crumb.