octadecanols

Octadecanol, commonly known as stearyl alcohol, is a long-chain fatty alcohol with 18 carbon atoms (C18H38O). It is a primary alcohol consisting of a straight-chain octadecyl group attached to a terminal hydroxyl group. In its pure form, octadecanol is a waxy solid at room temperature and exhibits a relatively high melting point compared with short-chain alcohols. It is insoluble in water but dissolves in many organic solvents, such as ether and chlorinated hydrocarbons, reflecting its predominantly hydrophobic character.

Occurrence and production

Octadecanol occurs in nature in small amounts in some fats and oils. Industrially, it is produced by hydrogenation of stearic acid or reduction of esters derived from natural fats and oils. The material is also obtainable via chemical transformations of fatty acids or their derivatives, and it is often supplied as a purified waxy chemical for use in various formulations.

Uses and applications

In cosmetics and personal care products, octadecanol serves mainly as an emollient, thickener, and texture enhancer in creams, lotions, lip balms, and hair care products. It acts as a waxy stabilizer and helps adjust viscosity and spreadability. Beyond cosmetics, it is used as a lubricant additive and in the manufacture of waxes, polishes, and some industrial lubricants. It can also function as an intermediate in the synthesis of esters for fragrances or surfactants.

Safety and regulation

Octadecanol is widely used in cosmetic products and is generally considered to have low acute toxicity. It is largely inert on the skin in typical formulations, though high concentrations can cause irritation. As a long-chain fatty alcohol, it is expected to be biodegradable and has a favorable environmental profile when properly handled and disposed of.