Steareth-20 is a chemical compound, carbon chains alkyl polyethylene glycol (PEG (Polyethylene glycol)) ether of ethoxylated fatty stearyl alcohol (20 mol), from palm kernel oils and coconut oils and fats.

The name describes the structure of the molecule:

• Steareth refers to ethoxylated stearyl alcohol fatty alcohols, which are ethoxylated to improve their water solubility and emulsifying properties.
• 20 indicates the average number of ethylene oxide units (a component of PEG) added in the ethoxylation process. This process makes the compound more water-soluble and improves its emulsifying properties. The number appearing after the name Steareth represents the molecular weight and the higher this number is, the less it penetrates the skin.

Raw Materials and Their Functions

Stearyl Alcohol. A fatty alcohol derived from natural fats and oils, used as the base for the production of Steareth-20. It provides the lipid component of the compound.

Ethylene Oxide. A chemical compound used to ethoxylate stearyl alcohol. The "20" in Steareth-20 indicates the average number of ethylene oxide units added to the stearyl alcohol.

Industrial Chemical Synthesis of Steareth-20

• Ethoxylation. The reaction of stearyl alcohol with ethylene oxide. During this reaction, ethylene oxide molecules are added to the stearyl alcohol, forming the polyethylene glycol ether known as Steareth-20.
• Reaction Control. The ethoxylation reaction is carefully controlled to ensure that the correct number of ethylene oxide units is added to the stearyl alcohol, achieving the desired properties in the final product.
• Purification. After the ethoxylation process, Steareth-20 is purified to remove any unreacted materials, impurities, and by-products.
• Quality Control. The purified Steareth-20 undergoes quality checks to ensure it meets the required standards. After quality control, it is packaged for use in various cosmetic and personal care products, where it serves as an emulsifier, surfactant, and solubilizer.

Form and color

Steareth-20 is typically a waxy solid or a paste. This compound is usually white or slightly yellowish.

What it is used for and where

Cosmetics

Cleaning agent. Ingredient that cleanses skin without exploiting the surface-active properties that produce a lowering of the surface tension of the stratum corneum. 

Surfactant - Cleansing agent. Cosmetic products used to cleanse the skin utilise the surface-active action that produces a lowering of the surface tension of the stratum corneum, facilitating the removal of dirt and impurities. 

Surfactant - Emulsifying agent. Emulsions are thermodynamically unstable. Emulsifiers have the property to reduce the oil/water or water/oil interfacial tension, improve emulsion stability and also directly influence the stability, sensory properties and surface tension of sunscreens by modulating their filmometric performance.

CAS: 9005-00-9 generic

Safety.

The term 'eth' refers to the ethoxylation reaction with ethylene oxide after which residues of ethylene oxide and 1,4-dioxane, chemical compounds considered carcinogenic, may remain. The degree of safety therefore depends on the degree of purity of the compound obtained. At present, no manufacturer is known to provide this information on the label.