Semi-synthetic lubricating oil composition

Abstract

A synthetic lubricating oil composition comprising a major portion of a synthetic lubricant component or a mixture of a synthetic lubricant component and a hydrocarbon mineral base oil and a minor portion of various additive components is described. The synthetic lubricant component is manufactured from internal olefins. The process for making the synthetic lubricant component utilizes boron trifluoride catalysis with a promoter to produce oligomer mixtures that have surprisingly low viscosities at low temperatures and surprisingly high viscosity indexes as compared with the oligomers found in other methods. It is important that internal olefins be used predominantly to make the oligomers. Alpha olefins make up the balance of the olefins.