Trideceth-18 is a chemical compound, 13 carbon chains alkyl polyethylene glycol (PEG (Polyethylene glycol)) ether of ethoxylated fatty Tridecyl alcohol.

The name describes the structure of the molecule

• Tridec refers to tridecyl alcohol, a fatty alcohol with a chain of 13 carbons, which forms the basis of the molecule.
• -eth indicates that ethylene oxide units have been added to the molecule.
• -18 means that, on average, 18 ethylene oxide units are added to each molecule of tridecyl alcohol.

Description of raw materials used in production

• Tridecyl alcohol. A fatty alcohol that can be sourced from vegetal origins or synthesized.
• Ethylene oxide. A highly reactive gaseous compound.

Step-by-step summary of industrial chemical synthesis process

• Preparation of tridecyl alcohol. Tridecyl alcohol, a fatty alcohol with a chain of 13 carbon atoms, is derived from natural sources or synthesised from petrochemical precursors.
• Ethoxylation. Tridecyl alcohol is reacted with ethylene oxide in the presence of a basic catalyst, typically potassium hydroxide.
• Neutralization. The product can be neutralized if necessary.
• Purification. The product may be purified via distillation or other methods to remove any impurities.

It appears as a colorless liquid or whitish gel.

What it is used for and where

Cosmetics

Emulsion stabilizer. Emulsions are thermodynamically unstable. Emulsion stabilisers improve the formation and stability of single and double emulsions. It should be noted that in the structure-function relationship, molar mass plays an important role.

Surfactant - Emulsifying agent. Emulsions are thermodynamically unstable and are used to soothe or soften the skin and emulsify, so they need a specific, stabilising ingredient. This ingredient forms a film, lowers the surface tension and makes two immiscible liquids miscible. A very important factor affecting the stability of the emulsion is the amount of the emulsifying agent. Emulsifiers have the property of reducing the oil/water or water/oil interfacial tension, improving the stability of the emulsion and also directly influencing the stability, sensory properties and surface tension of sunscreens by modulating the filmometric performance.

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. 

CAS   24938-91-8    69011-36-5

EC number    607-463-3   500-241-6

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.

Commercial Applications

Cosmetics and Personal Care Products. Trideceth-18 is often used as an emulsifying or solubilizing agent in cosmetic formulations, such as shampoos, body washes, and skin products.

Industry. It might be used in the manufacture of industrial soaps and cleansers due to its surfactant properties.

Medical Applications

Pharmaceuticals. While not a common ingredient in medicines, it might appear in some topical preparations due to its emulsifying capabilities.