Optimizing Dispersants in a Lubricant Formulation by Statistical Design - A Simplex Model

A simplex statistical design was used to model the Sequence VE engine performance of two dispersants, P and L, in a lubricant formulation. Dispersant P is a polyisobutylene succinimide, and L a low molecular weight ethylene propylene succinimide dispersant. The model showed that in the Sequence VE test, dispersant L gives superior sludge and varnish performance as compared to dispersant P. Furthermore, there is a synergism in the Sequence VE sludge performance when the two dispersants are mixed in the formulation.