Method of oxidatively degrading an olefinic polymer to produce an oxidised polymer product useful as a viscosity index improvement agent for a lubricating oil.

摘要

A method of oxidatively degrading an olefinic polymer comprises oxidising the olefinic polymer in an inert solvent in the absence of molecular oxygen and in the presence of an oxidant mixture of at least one peroxide and at least one hydroperoxide, said oxidant mixture being present in an amount sufficient to effect molecular weight degradation and the mole ratio of peroxide to hydroperoxide being in the range from 3.2 to 1 to 0.4 to 1, whereby an oxidised polymer product is obtained. The oxidised polymers produced by this method can be further reacted with a nitrogen-containing compound such as a polyalkylene polyamine. The oxidised polymer products are of value as viscosity index improvement agents when incorporated in lubricating oil compositions.