A rheological study of Viscosity Index Improvers (VII) in base oils under severe conditions
Résumé
The present work is dedicated to both experimental and modeling of the rheological behavior of lubricants simplified to polymer-base oil solutions. This analysis does not examine the impact of other additives even if they play a key role in viscosity. Rheological models are of main interest because they help oil manufacturers to formulate lubricants and predict their behavior at high temperature, high pressure and high shear stress. Moreover, the models can be included in elasto-hydrodynamic modeling to predict the film thickness in a contact.