Jojoba esters are the

hydrogenation Hydrogenation is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst such as nickel, palladium or platinum. The process is commonly employed to reduce or saturate organ ...

transesterification In organic chemistry, transesterification is the process of exchanging the organic group R″ of an ester with the organic group R' of an alcohol. These reactions are often catalyzed by the addition of an acid or base catalyst. The reaction ca ...

product of

Jojoba oil Jojoba oil is the liquid produced in the seed of the ''Simmondsia chinensis'' ( jojoba) plant, a shrub, which is native to southern Arizona, southern California, and northwestern Mexico. The oil makes up approximately 50% of the jojoba seed by w ...

. Jojoba Esters are commonly used in

cosmetic Cosmetic may refer to: *Cosmetics, or make-up, substances to enhance the beauty of the human body, apart from simple cleaning *Cosmetic, an adjective describing beauty, aesthetics, or appearance, especially concerning the human body *Cosmetic, a t ...

formulations as an

emollient A moisturizer, or emollient, is a cosmetic preparation used for protecting, moisturizing, and lubricating the skin. These functions are normally performed by sebum produced by healthy skin. The word "emollient" is derived from the Latin verb ''m ...

, due to its remarkable similarity to the natural oils produced by the human skin, and its high oxidative stability. Fully hydrogenated jojoba esters are most often small beads used to exfoliate the skin.

Chemical structure

Jojoba esters are proper waxes; there is no

triglyceride A triglyceride (TG, triacylglycerol, TAG, or triacylglyceride) is an ester derived from glycerol and three fatty acids (from ''wikt:tri-#Prefix, tri-'' and ''glyceride''). Triglycerides are the main constituents of body fat in humans and other ...

component of jojoba esters. Chemically, jojoba esters are a complex mixture of long chain

fatty acid In chemistry, particularly in biochemistry, a fatty acid is a carboxylic acid with an aliphatic chain, which is either saturated or unsaturated. Most naturally occurring fatty acids have an unbranched chain of an even number of carbon atoms, ...

s and fatty alcohols joined by an ester bond, resulting in a total length of 36 to 46 carbon atoms. Jojoba esters are produced by the interesterification of jojoba oil,

hydrogenated Hydrogenation is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst such as nickel, palladium or platinum. The process is commonly employed to reduce or saturate organic ...

jojoba oil, or a mixture of the two. Pure jojoba oil and pure hydrogenated jojoba oil are also correctly described as jojoba esters. The CTFA does not regard ''partially''-hydrogenated jojoba oil as jojoba esters. For this reason, jojoba esters must not contain any trans-unsaturation. Jojoba esters' chemical structure is very similar to that of human

sebum A sebaceous gland is a microscopic exocrine gland in the skin that opens into a hair follicle to secrete an oily or waxy matter, called sebum, which lubricates the hair and skin of mammals. In humans, sebaceous glands occur in the greatest nu ...

and of

whale oil Whale oil is oil obtained from the blubber of whales. Whale oil from the bowhead whale was sometimes known as train oil, which comes from the Dutch word ''traan'' (" tear" or "drop"). Sperm oil, a special kind of oil obtained from the head ...

Physical properties

Physically, jojoba esters are an odourless, colourless liquid, white cream, or hard white wax, with melting points ranging from 15 °C to 70 °C. Their texture and crystallinity may be modified by rapid cooling, thus altering their cosmetic properties. Jojoba esters are very resistant to

oxidation Redox (reduction–oxidation, , ) is a type of chemical reaction in which the oxidation states of substrate change. Oxidation is the loss of electrons or an increase in the oxidation state, while reduction is the gain of electrons or a ...

, more so than

castor oil Castor oil is a vegetable oil pressed from castor beans. It is a colourless or pale yellow liquid with a distinct taste and odor. Its boiling point is and its density is 0.961 g/cm3. It includes a mixture of triglycerides in which about ...

, coconut oil,

macadamia oil Macadamia oil (or macadamia nut oil) is the non-volatile oil collected from the nuts of the macadamia (''Macadamia integrifolia''), a native Australian plant. It is used in food as a frying or salad oil, and in cosmetic formulations as an emollien ...

, even many fractions of

mineral oil Mineral oil is any of various colorless, odorless, light mixtures of higher alkanes from a mineral source, particularly a distillate of petroleum, as distinct from usually edible vegetable oils. The name 'mineral oil' by itself is imprecise, ...

Uses

Jojoba esters are mainly used as emollients in

cosmetics Cosmetics are constituted mixtures of chemical compounds derived from either natural sources, or synthetically created ones. Cosmetics have various purposes. Those designed for personal care and skin care can be used to cleanse or protect ...

such as

lipstick Lipstick is a cosmetic product used to apply coloration and texture to lips, often made of wax and oil. Different pigments are used to produce color, and minerals such as silica may be used to provide texture. The use of lipstick dates back t ...

shampoos Shampoo () is a hair care product, typically in the form of a viscous liquid, that is used for cleaning hair. Less commonly, shampoo is available in solid bar format. Shampoo is used by applying it to wet hair, massaging the product into the ...

and moisturizing lotions. Jojoba esters may be ethoxylated to form such water-soluble materials as PEG-150 Jojoba, PEG-120 Jojoba, or PEG-80 Jojoba. Jojoba esters are excellent botanical substitutes for

and its derivatives, such as

cetyl alcohol Cetyl alcohol , also known as hexadecan-1-ol and palmityl alcohol, is a C-16 fatty alcohol with the formula CH3(CH2)15OH. At room temperature, cetyl alcohol takes the form of a waxy white solid or flakes. The name cetyl derives from the whale o ...

and spermaceti. Hydrolyzed jojoba esters (HJEs) are created via a saponification reaction which liberates more than 12 long chain fatty alcohols.

References

{{DEFAULTSORT:Jojoba Ester Cosmetics chemicals Waxes

Chemical structure

Physical properties

Uses

See also

References