| 摘要 |
<p>A viscosity index improver comprises a polymer soln. in a diluent oil of esters which are suitable as lubricants, esp., aliphatic diesters with Noack evapn. values 30%, pref. 20%, opt. with high-viscosity mineral lubricant oils. The solns. have higher shear resistance give lower increase in viscosity for the same improvement in viscosity index, and give improved engine performance. The esters have higher flash pts. The solns. have lower viscosity at about 50 degrees C, so that higher concns. of the polymers in the soln. can be used.</p> |
