Steareth- 21 (inci)

Stearethene (e) refers to the polyoxyethylene ethers of stearyl alcohol (octadecanol) (for comparison see: cetethe as polyoxyethylene ether of cetyl alcohol; laurethe as polyoxyethylene ether of lauryl alcohol and others).

Polyalkylene glycol ethers are non-ionic surfactants whose lipophilic part consists of fatty alcohols (e.g. lauryl alcohol, palmitic alcohol, stearyl alcohols etc.). The hydrophilic part is formed by short-chain polyethylene glycols (polyoxyethylene). In the designation of fatty alcohol polyglycol ethers, the inserted numbering means the average number of ethylene oxide units per mole. Steareth-21, for example, is the INCI designation for a polyoxyethylene ether with 21 ethylene oxide units per mole.

Steareth-21 is used in cosmetic formulations. The mixture of substances acts as a surfactant (washing-active substance; improves the even distribution of the products during application).