Sodium stearate

Description

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.

Description

Humans began to use cleaning substances that resemble modern soaps almost five millennia ago. Early crude soaps were made from natural fats and oils and available alkaline materials such as wood ashes. During the Industrial Revolution, manufacturers began to make more refined soaps from purified fatty acids and alkalis such as lye (sodium or potassium hydroxide), quicklime (calcium oxide), or slaked lime (calcium hydroxide).
Sodium stearate is the most common fatty acid salt in today’s soaps. Common sources of the starting material, stearic acid, are vegetable triglycerides obtained from coconut and palm oils and animal triglycerides from tallow. The names stearic and stearate are derived from stéar, the Greek word for tallow.
Besides being a major soap component, sodium stearate is used as an additive in other cosmetic products to form solid “stick” shapes. According to Acme-Hardesty, a Blue Bell, PA–based manufacturer of biobased products, sodium stearate has a wide range of additional uses, including
Many Web sites provide recipes for making soap at home. But all scratch recipes require lye, which is better off being handled in the lab. If you are willing not to make soap from scratch, you can purchase a “melt and pour” soap, in which the desired oil or fat is already treated with lye. Happy soapmaking!

Chemical properties

white to off-white powder

Chemical properties

Sodium stearate, NaC18H35O2, white solid, 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.

The Uses of Sodium stearate

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.

The Uses of Sodium stearate

β-Lactamase inhibitor

The Uses of Sodium stearate

Pharmaceutic aid (emulsifying and stiffening agent). In glycerol suppositories; also in toothpaste; as waterproofing agent.

The Uses of Sodium stearate

Sodium Stearate is the sodium salt of stearic acid. it functions as a binder, emulsifier, and anticaking agent. it is used as a plasticizer in chewing gum base.

The Uses of Sodium stearate

Characteristic of soaps, sodium stearate has both hydrophilic and hydrophobic parts, the carboxylate and the long hydrocarbon chain, respectively. These two chemically different components induce the formation of micelles, which present the hydrophilic heads outwards and their hydrophobic (hydrocarbon) tails inwards, providing a lipophilic environment for hydrophobic compounds. It is also used in the pharmaceutical industry as a surfactant to aid the solubility of hydrophobic compounds in the production of various mouth foams.

Definition

ChEBI: An organic sodium salt comprising equal numbers of sodium and stearate ions.

Production Methods

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.

Safety Profile

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

Purification Methods

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.]