• Branched-chain fatty acids;
  • Iso-oleic acid;
  • Isostearic acid;
  • Lubricants;
  • Methyl iso-oleate


Iso-oleic acid is a mixture of C18-unsaturated branched-chain fatty acid isomers with a methyl group on various positions of the alkyl chain, which is the product of the skeletal isomerization reaction of oleic acid and is the intermediate used to make isostearic acid (C18-saturated branched-chain fatty acid isomers). Methyl iso-oleate, a mixture of C18-unsaturated branched-chain fatty acid methyl ester isomers, is obtained via acid catalyzed esterification of iso-oleic acid with methanol. The branched-chain materials are liquid at room temperature and their “oiliness” property makes them an attractive candidate for the lubricant industry. In this paper, we report characterization of these branched-chain materials using comprehensive two-dimensional GC with time-of-flight mass spectrometry (GC × GC/TOF-MS) and their physical and lubricity properties using tribology measurements.