Location: Bio-oils ResearchTitle: Derivatization of castor oil based estolide esters: Preparation of epoxides and cyclic carbonates
Submitted to: Industrial Crops and Products
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/30/2017
Publication Date: 5/5/2017
Publication URL: https://handle.nal.usda.gov/10113/5684918
Citation: Doll, K.M., Cermak, S.C., Kenar, J.A., Walter, E.L., Isbell, T.A. 2017. Derivatization of castor oil based estolide esters: Preparation of epoxides and cyclic carbonates. Industrial Crops and Products. 104:269-277.
Interpretive Summary: ARS has been developing many vegetable oil based lubricants in recent years. One of the more successful projects has been the creation of a compound called an estolide which is now being used by a commercial partner for a variety of applications. This technology has been expanded by a chemical reaction which adds a group called a cyclic carbonate to the estolide. This manuscript builds further on this methodology, and adds cyclic carbonates to estolides which have been made from several different vegetable oils. The new materials have a range of viscosities and pour points making them a versatile starting point for industrial lubricant formulations, a benefit to lubrication manufacturers, their customers, and especially to producers of natural oils.
Technical Abstract: Estolides that are based on castor oil and oleic acid are versatile starting points for the production of industrial fluids with new properties. A variety of unsaturated estolides were derivatized by epoxidation with hydrogen peroxide. The epoxidized estolides were further modified using supercritical carbon dioxide and tetrabutylammonium bromide to chemically incorporate carbon dioxide into the structure, thus yielding a 5-membered cyclic carbonate structure. These new epoxides and cyclic carbonates exhibited higher pour points, oxidation onset temperatures, and viscosities compared to the corresponding unsaturated precursors. One derivative (cas-oleic TAG) had a dynamic viscosity of ~9000 mPa s at 40 deg C, demonstrating potential for use in industrial applications.