ACID-CATALYZED CONDENSATION OF OLEIC-ACID INTO ESTOLIDES AND POLYESTOLIDES

Oleic acid, when treated with 1.0 equivalent of perchloric acid at 50 degrees C, produced a 76% yield of polyestolide. The concentration of mineral acid greatly affected the rate of estolide formation, with increased rates under high acid concentrations. Over a range of temperatures from room temperature to 100 degrees C, reaction rates increased at higher temperatures. However, high acid concentrations and temperatures produced undesirable side products, primarily lactones. Other acids catalyze the condensation of oleic acid to form estolide with the following relative rates: HC1O(4) > H2SO4 > p-toluenesulfonic > BF3.Et(2)O > montmorillonite K.10 > HC1 > H3PO4, HNO3. Addition of water impedes the formation of estolide.