Synthesis and Physical Properties of Potential Biolubricants based on Ricinoleic Acid

The desire to replace petroleum‐based materials with environmentally friendly and sustainable alternatives has stimulated the development of vegetable oil‐based materials as biolubricants. Our studies have focused on molecules that might be produced by biosynthesis of genetically altered oilseed plants with limited post‐harvest modification. Various ricinoleate and 12‐hydroxystearate esters and estolides were synthesized and their melting points and viscosities were documented. The antifriction and antiwear properties of some esters were evaluated with a microtribometer. The purities of all the products were >98–99% by gas chromatography. Some of these compounds showed melting points, viscosities, and lubricity suitable for uses as biolubricants. Various ricinoleate esters acylated at the 12 positions with short‐chain acids were particularly promising.