ALUMINUM MONOSTEARATE

Chemical Properties

Aluminum monostearate is an aluminum compound of stearic acid and palmitic acid. The USP32–NF27 states that aluminum monostearate contains the equivalent of not less than 14.5% and not more than 16.5% of Al₂O₃, calculated on the dried basis. The JP XV states that it contains not less than 7.2% and not more than 8.9% of aluminium.
Aluminum monostearate occurs as a white, fine, bulky powder with a slight odor of fatty acid. It is a solid material.

Chemical Properties

Fine, white to yellowish-white powder; faint characteristic odor. Insoluble in water, alcohol, and ether. Forms a gel with aliphatic and aromatic hydrocarbons.

Uses

Paints, inks, greases, waxes, thickening lubricating oils; waterproofing, gloss producer, stabilizer for plastics, food additive.

Uses

Used for the packaging of pharmaceuticals, and in the preparation of colors for cosmetics.

Production Methods

Aluminum monostearate is prepared by reacting aluminum with stearic acid.

Definition

A complex containing aluminum and dextran, a chain of molecular weight 2500, corresponding to a chain of 15 anhydroglucose units.

Pharmaceutical Applications

Aluminum monostearate is mainly used in microencapsulation and in the manufacture of ointments. Aluminum monostearate is used as a viscosity-increasing agent in nonaqueous cosmetic and pharmaceutical formulations. In addition, aluminum monostearate can be used as an emulsion stabilizer in cosmetic emulsions and is used in cosmetics such as mascara, moisturizers, and sunscreens.

Safety Profile

A nuisance dust. When heated to decomposition it emits acrid smoke and fumes. See also ALUMINUM COMPOUNDS.

Safety

Aluminum monostearate is generally regarded as relatively nontoxic and nonirritant when used as an excipient.

storage

Aluminum monostearate should be stored in a well-closed container in a cool, dry, place. It is stable under ordinary conditions of use and storage.

Regulatory Status

Aluminum monostearate and aluminum stearate are included in the FDA Inactive Ingredients Database (oral capsules and tablets, topical creams and ointments). Included in nonparenteral medicines licensed in the UK.