Products from Castor Oil

Castor oil has a long history and special status relative to other vegetable oils. Castor oil seeds have been found in Egyptian graves of 4000 BC. The more sophisticated downstream products are more valuable than the long-established and local uses of the oil. The historical procedure for splitting the C₁₈ricinoleic acid chain into C₇ and C₁₁ fragments suffered from low yields and high environmental pollution. All highly unsaturated oils such as linseed undergo atmospheric oxidation when blown, that is, heated in air. Hydrogenated castor oil and hydrogenated castor acids have higher melting points than the nonhydrogenated materials. Reaction of the hydroxyl group in castor oil with ethylene or propylene oxide gives rise to a nonionic surfactant. Like other hydroxyl-containing molecules, castor oil reacts with appropriate isocyanates to produce polyurethanes, which find many uses in the developed world.