The presence of a hydroxyl group, in addition to an olefinic linkage, in the predominating fatty acid of castor oil gives this vegetable oil many unique and interesting properties. Castor oil consists largely of glycerides of ricinoleic acid or 12‐hydroxy octadecenoic acid. The chemical reactions of castor oil, undecylenic acid, 12‐hydroxylstearic acid, sebacic acid, and nylon 11, depict the uniqueness of this agricultural oil. By dehydration, castor oil is converted to a conjugated acid oil similar to tung or oiticica oil. The catalytic dehydration results in the formation of a new double bond in the fatty acid chain. The dehydrated castor oil imparts good flexibility, rapid dry, excellent color retention, and water resistance to protective coatings. The pyrolysis of castor oil cleaves the molecule to produce undecylenic acid and heptaldehyde. The pyrolysis of the methyl ester at 450–550 C results in the formation of methyl 10‐undecylenate. Hydrolysis of the methyl ester gives 10‐undecylenic acid. Hydrogen bromide is added to form 11‐bromo undecanoic, which is ammoniated and condensed to form a nylon polymer. When castor oil is added slowly to an 80% caustic solution, the sodium ricinoleate formed splits to form sodium sebacate and capryl alcohol. Sebacic acid is condensed with hexamethylene diamine to form nylon 6,10. The commercial application of castor oil derivatives in urethanes, starch gel modifiers, medium chain triglycerides, and thixotropic additives is reviewed briefly.

Castor oil is derived from the bean of the castor plant, Ricinus communis . The seeds of the castor plant are produced in racemes or clusters of capsules. The capsules contain three seeds protected by a hull that is removed prior to processing. Commercial processing of the seed consists of heating the seed, crushing, and then processing in solvent extraction units. The recovery of the oil produced goes through four stages to produce a better quality oil. Stages are degumming, removal of free fatty acids, deodorization, and decolorization. India is the largest producer of castor seeds in the world. Arkema is the world's largest user of castor oil for one product (Rilsan Nylon 11).The toxicological properties of castor oil have not been fully studied. Castor seed are highly toxic. Uses for castor oil are numerous; preparation of nylon 11, urethanes, in surface coatings, lubricants, textiles, cosmetics, surfactants and dispersants, and biofuels.

Castor oil, a renewable vegetable oil resource derived from the seed of Ricinus communis , is a versatile material that finds use as an industrial article of commerce. Castor oil is the only principal industrial oil that consists of 90% of the glyceride of a hydroxy acid, ricinoleic acid. The presence of the hydroxyl group in addition to the olefinic linkage, accounts for a unique combination of physical and chemical properties. World production, processing, and utilization of the oil to produce a variety of oleochemcals, are described as are the properties and chemical modifications of castor oil and its derivatives. Processes for recovery of the oil and meal, dehydration, polyamide polymer formation, sulfonation, alkali fusion, pyrolysis, hydrogenation, alkoxylation, and urethane reactions are discussed, and applications for the various materials are presented.

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The use of fillers in polyolefin polymer composites has escalated in recent years in conjunction with the need for improved physical properties and the increased costs of petroleum-based polymers. Fillers, used as inert extenders and reinforcing agents, present problems when added to organic polymers that are different in chemical nature and physical form. Use of surface-treatment additives has been developed to overcome problems that originate in the interfacial region where the organic resin phase must wet out the inorganic filler being compounded. Achieving optimal physical and chemical properties in a filled compound, by the use of hydrophobic esters derived from castor oil as wetting and encapsulating agents, was evaluated. The hydrophobic esters improved the dispersion and distribution of filler particles throughout the organic medium. The surface treatment with the esters resulted in a lowering of viscosity and better ability to control the rheology of the compound, raise the extender filler loadings and an upgrading of mechanical properties of the filled resin. It was shown that the use of hydrophobic esters as a surface filler treatment resulted in increased tensile strength, higher impact strength and improved processing of filled polymer composites.