Натрий стеарат

Описание

Sodium stearate is the sodium salt of stearic acid. This white solid is the most common soap. It is found in many types of solid deodorants, rubbers, latex paints, and inks. It is also a component of some food additives and food flavorings.

Химические свойства

Sodium stearate, NaC18H35O2, white to off-white powder, soluble, froth or foam upon shaking the water solution (soap), formed by reaction of NaOH and stearic acid (in alcoholic solution) and evaporating. Used as a source of stearate.

Использование

sodium stearate is a fatty acid used as a waterproofing agent. Sodium stearate is one of the least allergy-causing sodium salts of fatty acids. It is non-irritating to the skin.

Методы производства

Sodium stearate is produced as a major component of soap upon saponification of oils and fats. The percentage of the sodium stearate depends on the ingredient fats. Tallow is especially high in stearic acid content (as the triglyceride), whereas most fats only contain a few percent. The idealized equation for the formation of sodium stearate from stearin (the triglyceride of stearic acid) follows :
(C₁₈H₃₅O₂)₃C₃H₅ → C₃H₅(OH)₃ + 3 C₁₇H₃₅CO₂Na
Purified sodium stearate can be made by neutralizing stearic acid with sodium hydroxide.

Определение

ChEBI: Sodium octadecanoate is an organic sodium salt comprising equal numbers of sodium and stearate ions. It has a role as a detergent. It contains an octadecanoate.

Профиль безопасности

Poison by intravenous route. When heated to decomposition it emits toxic fumes of Na2O.

Методы очистки

It is better to prepare it by adding a slight excess of octadecanoic acid to ethanolic NaOH, evaporating and extracting the residue with dry Et2O. [Beilstein 2 III 1003.]