摘要 |
Use of a lubricant in a diesel engine to disperse soot produced by the diesel engine, the soot being dispersed without adversely affecting the viscosity of the lubricant; the lubricant comprising a dispersant and a functionalised viscosity index improver; the functionalised viscosity index improver comprising a highly functionalised graft copolymer reaction product of an oxygen, a nitrogen or an oxygen and nitrogen containing, ethylenically unsaturated, aliphatic or aromatic monomer having from 2 to about 50 carbon atoms grafted on to a polyolefin copolymer. |