Ethyl macadamiate is the

ester In chemistry, an ester is a compound derived from an oxoacid (organic or inorganic) in which at least one hydroxyl group () is replaced by an alkoxy group (), as in the substitution reaction of a carboxylic acid and an alcohol. Glycerides a ...

ethyl alcohol Ethanol (abbr. EtOH; also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is an organic compound. It is an alcohol with the chemical formula . Its formula can be also written as or (an ethyl group linked to a hyd ...

and the

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 derived from ''

Macadamia ternifolia ''Macadamia ternifolia'' (common names: small-fruited Queensland nut, gympie nut) is a tree in the flowering plant family Proteaceae, native to Queensland in Australia, and is listed as vulnerable under the EPBC Act. ''Macadamia ternifolia'' is ...

'' seed oil. Ethyl macadamiate is used in some cosmetic formulations.

Chemical structure

Ethyl macadamiate is a mixture of the ethyl esters of the free fatty acids produced by the complete

saponification Saponification is a process of converting esters into soaps and alcohols by the action of aqueous alkali (for example, aqueous sodium hydroxide solutions). Soaps are salts of fatty acids, which in turn are carboxylic acids with long carbon chains. ...

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 ...

. The primary constituents of ethyl macadamiate are

ethyl oleate Ethyl oleate is a fatty acid ester formed by the condensation of oleic acid and ethanol. It is a colorless oil although degraded samples can appear yellow. Use and occurrence Additive Ethyl oleate is used by compounding pharmacies as a vehicle ...

and ethyl palmitoleate.

Physical properties

Ethyl macadamiate is a clear, colorless liquid at room temperature, with a typical fatty

odor. Ethyl macadamiate's melting (congealing) point is and its

specific gravity Relative density, or specific gravity, is the ratio of the density (mass of a unit volume) of a substance to the density of a given reference material. Specific gravity for liquids is nearly always measured with respect to water at its densest ...

is 0.88. Ethyl macadamiate spreads very aggressively, and has a light, nongreasy dry skinfeel similar to that of some silicone derivatives, however, ethyl macadamiate is non-volatile.

Uses

Ethyl macadamiate is used 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 ...

, especially in

skincare Skin care is a range of practices that support skin integrity, enhance its appearance, and relieve skin conditions. They can include nutrition, avoidance of excessive sun exposure, and appropriate use of emollients. Practices that enhance appea ...

, haircare and suncare formulation. The dry skinfeel and high spread make ethyl macadamiate well suited for increasing sunscreen coverage. Ethyl macadamiate is an alternative to cyclomethicone and

dimethicone Polydimethylsiloxane (PDMS), also known as dimethylpolysiloxane or dimethicone, belongs to a group of polymeric organosilicon compounds that are commonly referred to as silicones. PDMS is the most widely used silicon-based organic polymer, as i ...

as a skinfeel modifier where a botanical, nonvolatile and/or lipid-soluble substance is preferred.

References

{{reflist Cosmetics chemicals Ethyl esters Fatty acid esters