Sodium stearate is the sodium salt of stearic acid, appearing as a fine, white powder or granules with a faint odor. It is a surfactant and emulsifier, widely used in personal care products, pharmaceuticals, and industrial applications.
Chemical Name and CAS Registry Number: Sodium octadecanoate [822-16-2]
Functional Category: Surfactant, emulsifying agent, stabilizer, lubricant
Identification: Complies with pharmacopeial standards
Solubility: Soluble in water, forming a colloidal solution; insoluble in organic solvents
pH (1% solution): 8.0–10.0
Loss on Drying: ≤5.0%
Heavy Metals: ≤0.002%
Residual Solvents: Complies with regulatory limits
Sodium stearate functions as a lubricant, emulsifier, and stabilizer in pharmaceutical formulations. It is used in topical preparations, tablet formulations, and suppositories, enhancing the spreadability and texture of creams and lotions while providing structural integrity in solid dosage forms.
Sodium stearate is a well-tolerated excipient with a long history of safe use. Its surfactant properties make it useful in various formulations, though it may interact with certain drug compounds, potentially affecting dissolution rates.
