Castor oil
is a vegetable oil extracted from castor beans. It is a colorless to very pale yellow liquid with a distinct taste and aroma. Its boiling point is 313 °C (595 °F), and its density is 0.961 g/cm3. It includes a mixture of triglycerides, about 90% of the fatty acids are ricinolates, and the other important constituents are oleate and linoleic.
Castor oil and its derivatives are used in the manufacture of soaps, lubricants, hydraulic fluids, brake fluids, paints, dyes, coatings, inks, cold-resistant plastics, waxes, polishes, nylon, pharmaceuticals, and perfumes.
Study the origins of the word
The name most likely comes from confusing the ricinus plant that produces it with another plant, Vitex agnus castus. However, an alternative etymology indicates its use as a substitute for castoreum.
installation
Castor oil is known as a source of ricinoleic acid, which is an 18-carbon monounsaturated fatty acid. Among the fatty acids, ricinoleic acid is unique, as it has a hydroxyl functional group on the twelfth carbon atom. This functional group causes ricinoleic acid (and castor oil) to be more polar than most fats. The chemical reaction of the alcohol group also allows for chemical derivation that is not possible with most other seed oils. Castor oil is a valuable feedstock chemical, due to its ricinoleic acid content, commanding a higher price than other seed oils. For example, in July 2007, Indian castor oil sold for $0.90 per kg ($0.41 per pound), while US soybean, sunflower, and canola oils sold for $0.30 per kg ($0.14 per pound).
Food and preservatives
In the food industry, food grade castor oil is used in food additives, flavorings, candy (eg, polyglycerol polyricinoleates in chocolate), as a mold inhibitor and in packaging. Polyoxyethyl castor oil (eg, Colifor EL) is also used in the food industry.
In India, Pakistan and Nepal, food grains are preserved with castor oil. Prevents rotting of rice, wheat and legumes. For example, Indian legume peas are usually available coated in oil for longer storage.
Traditional medicine
The Ebers Papyrus attested to the use of castor oil as a laxative around 1550 BC, and it was used several centuries ago.
Although it has been used in traditional medicine to induce labor in pregnant women, there is no clinical evidence that castor oil is effective in dilating the cervix or inducing labour.
Alternative therapeutic use
According to the American Cancer Society: "Available scientific evidence does not support claims that castor oil applied to the skin treats cancer or any other disease."
Skin and hair care
Castor oil has been used in cosmetics, in creams, and as a moisturizer. Small amounts of castor oil are often used in cold process soaps, to increase the lather in the finished bar. It is also used to enhance hair conditioning in other products and for its supposed anti-dandruff properties.
coatings
Castor oil is used as a bio-based polyol in the polyurethane industry. The average functional group (number of hydroxyl groups per triglyceride molecule) of castor oil is 2.7, so it is widely used as a solid polyol and in coatings. One particular use is in polyurethane concrete, where the castor oil emulsion reacts with an isocyanate (usually Methylene Diphenyl Diisocyanate), cement and building aggregates. This applies fairly thickly like mortar, and is self-leveling. This base is covered with other resilient floor construction systems.
Castor oil is not a drying oil, which means that it has a lower air interaction compared to other oils such as linseed oil and tung oil. The drying of castor oil yields linoleic acids, which have drying properties. In this process, the hydroxyl group on ricinoleic acid is removed along with the hydrogen from the next carbon atom, resulting in a double bond with oxidative bonding properties that produces drying oil.