POTASSIUM STEARATE

Potassium Stearate is the potassium salt of stearic acid and belongs to the class of long-chain anionic surfactants commonly known as potassium soaps.

Potassium Stearate functions as a cleansing agent, emulsifier, foam modifier, lubricant, and processing aid in personal care and industrial formulations.

Potassium Stearate combines a hydrophobic C18 hydrocarbon chain with a hydrophilic potassium carboxylate group, enabling it to interact with both aqueous and oily phases.

CAS Number: 593-29-3

EC Number: 209-786-1

Molecular Formula: C₁₈H₃₅KO₂

Molecular Weight: 322.57 g/mol

SYNONYMS:

Potassium Stearate, Stearic Acid Potassium Salt, Stearic Acid Potassium Salt (1:1), Octadecanoic Acid Potassium Salt, Octadecanoic Acid Potassium Salt (1:1), Potassium Octadecanoate, Potassium n-Octadecanoate, Potassium Octadecanoate(1-), Potassium Salt of Octadecanoic Acid, Potassium Salt of Stearic Acid, Potassium Soap of Stearic Acid, Stearate of Potassium, Potassium Monostearate, Potassium Hydrogen Stearate, Potassium Octadecanoic Acid Salt, Potassium C18 Fatty Acid Salt, C18 Potassium Soap, Long-Chain Potassium Carboxylate, Potassium Fatty Acid Soap, Potassium Fatty Acid Salt, Anionic Potassium Soap, Potassium Metallic Soap, Potassium Carboxylate Surfactant, Potassium Stearate Soap, INCI Potassium Stearate, Potassium Stearate OPK-1000, Potassium Stearate OPK®-1000, DUB SK, Steadan 300, SPO 100, Rexanol, Nonsoul SK-1, Nonsoul MK-2, Octadecanoic Acid, Potassium Salt, Potassium Octadecanoate Salt, Potassium Stearate 593-29-3, EC 209-786-1, MFCD00072385, UNII 17V812XK50, C₁₈H₃₅KO₂, C18H35KO2, ANBFRLKBEIFNQU-UHFFFAOYSA-M, Potassium; Octadecanoate, Potassium Stearate Powder, Potassium Stearate Crystals, Cosmetic-Grade Potassium Stearate, Industrial-Grade Potassium Stearate, Pharmaceutical-Grade Potassium Stearate, High-Purity Potassium Stearate

APPLICATIONS

Potassium Stearate serves as an anionic cleansing agent in personal care formulations designed to remove oils, dirt, and particulate contamination from the skin.
Potassium Stearate supports the preparation of liquid and semi-solid soaps requiring greater water compatibility than comparable sodium stearate systems.

Potassium Stearate promotes the formation of stable, creamy lather in shaving soaps formulated for brush or hand application.
Potassium Stearate contributes to the dense foam and lubricating character of shaving creams, helping the razor move more smoothly across the skin.

Potassium Stearate enables shaving products to combine cleansing action, foam generation, emulsion stability, and suitable application rheology.
Potassium Stearate functions as a surfactant in facial cleansers intended to disperse sebum and water-insoluble impurities.

Potassium Stearate provides cleansing activity in body washes, hand cleansers, and rinse-off personal hygiene products.
Potassium Stearate facilitates the production of soap-based cleansing lotions with controlled viscosity and uniform appearance.

Potassium Stearate supports powder shampoos that develop cleansing action and foam after being mixed with water.
Potassium Stearate contributes to hair-cleansing formulations by helping water interact with oily residues present on the hair and scalp.

Potassium Stearate acts as an emulsifier in cosmetic creams containing both aqueous and oil-soluble ingredients.
Potassium Stearate helps stabilize oil-in-water emulsions by positioning its hydrophilic carboxylate group in the aqueous phase and its hydrocarbon chain in the oil phase.

Potassium Stearate promotes uniform distribution of emollients, fragrances, oils, and other hydrophobic ingredients throughout suitable cosmetic formulations.
Potassium Stearate supports lotions that require simultaneous emulsification, cleansing, and viscosity development.

Potassium Stearate enables formulators to adjust the body and consistency of soap-based creams through concentration, temperature, and electrolyte control.
Potassium Stearate contributes to foam stabilization in rinse-off products where persistent, fine-textured lather is desirable.

Potassium Stearate facilitates the incorporation of fatty materials into alkaline cleansing systems.
Potassium Stearate assists in dispersing perfume oils and other compatible oil-soluble components in aqueous soap formulations.

Potassium Stearate functions as a co-emulsifier alongside compatible nonionic, amphoteric, or anionic surfactants.
Potassium Stearate provides a naturally derived fatty-acid-based surfactant option when manufactured from appropriately sourced stearic acid.

Potassium Stearate serves as a soap component in specialty handwashing formulations designed for industrial and institutional environments.
Potassium Stearate supports the manufacture of soft soaps that remain more workable and water-compatible than hard sodium-soap systems.

Potassium Stearate promotes wetting in cleaning formulations by lowering interfacial tension between water and oily surfaces.
Potassium Stearate contributes to soil suspension by surrounding detached oily material and helping prevent immediate redeposition.

Potassium Stearate enables the preparation of alkaline cleaning compositions for selected household and professional applications.
Potassium Stearate functions as an emulsifying ingredient in pharmaceutical creams and topical bases when the selected grade complies with applicable pharmaceutical requirements.

Potassium Stearate supports ointment and lotion systems in which a fatty-acid soap is required to stabilize the dispersed phase.
Potassium Stearate can provide lubricating action during tablet or compact production when validated for the specific formulation and processing equipment.

Potassium Stearate assists powder processing by reducing friction between selected formulation components and manufacturing surfaces.
Potassium Stearate contributes to release performance in compressed products where adhesion to punches or dies must be controlled.

Potassium Stearate serves as an emulsifier or processing aid in selected regulated food formulations when an appropriate food-grade product is used and local legislation permits the application.
Potassium Stearate supports the uniform distribution of lipid components in suitable food emulsions.

Potassium Stearate provides lubricating or release properties in selected confectionery-processing operations where regulatory approval and grade documentation are established.
Potassium Stearate can assist the processing of aerated or whipped formulations by influencing interfacial behavior and foam structure.

Potassium Stearate facilitates the controlled dispersion of fatty ingredients in specialized food systems when used within applicable legal limits.
Potassium Stearate functions as an emulsifying soap in aqueous polymerization and latex-production systems.

Potassium Stearate helps stabilize dispersed polymer particles during selected emulsion-polymerization processes.
Potassium Stearate supports acrylate rubber formulations that use soap-based emulsification or soap-sulfur vulcanization technology.

Potassium Stearate contributes to the processing of natural and synthetic rubber compounds by providing interfacial lubrication.
Potassium Stearate facilitates release of selected rubber articles from molds when incorporated at an optimized concentration.

Potassium Stearate reduces adhesion between polymer compounds and processing equipment in suitable extrusion and molding operations.
Potassium Stearate functions as an internal or external lubricant in selected thermoplastic formulations.

Potassium Stearate promotes improved flow during polymer processing by reducing friction between compound particles and metal surfaces.
Potassium Stearate assists mold release in plastic formulations where a water-compatible fatty-acid salt is preferred.

Potassium Stearate supports pigment and filler dispersion by improving wetting within compatible aqueous or polymer-based systems.
Potassium Stearate contributes to more uniform distribution of functional additives in selected rubber and plastic compounds.

Potassium Stearate serves as a soap-type emulsifier in specialty cutting fluids and metalworking compositions.
Potassium Stearate provides mild lubricating properties in aqueous industrial fluids where fatty-acid soaps are compatible with the operating conditions.

Potassium Stearate supports textile-processing formulations as an emulsifying, wetting, or softening component.
Potassium Stearate assists in the preparation of oiling agents used to distribute lubricating materials over textile fibers.

Potassium Stearate contributes to paper-processing formulations requiring emulsification or controlled deposition of hydrophobic ingredients.
Potassium Stearate functions as an emulsifier in selected adhesives, coatings, and waterborne dispersions.

Potassium Stearate facilitates preparation of pigment concentrates and aqueous dispersions when its alkaline soap character is compatible with the formulation.
Potassium Stearate serves as a laboratory reagent and a source of stearate ions in chemical synthesis, surface studies, and materials research.

Potassium Stearate enables the preparation of other stearate compounds through ion-exchange or precipitation reactions with suitable metal salts.
The principal cosmetic functions of Potassium Stearate are cleansing, emulsifying, and surfactant activity. Supplier formulations also demonstrate its use in powder shampoo and shaving-cream systems, while fatty-acid-salt manufacturers supply potassium stearates to personal care, pharmaceutical, plastic, rubber, paper, and food-related markets.

DESCRIPTION

Potassium Stearate is an organic potassium compound produced by replacing the acidic hydrogen of stearic acid with a potassium ion.
Structurally, Potassium Stearate consists of a long, essentially linear eighteen-carbon hydrocarbon chain attached to a carboxylate group.

The carboxylate group carries a negative charge that is ionically associated with potassium.
This amphiphilic structure gives Potassium Stearate a hydrophobic fatty chain and a hydrophilic ionic head group.

Because of this molecular arrangement, Potassium Stearate accumulates at interfaces between water, oils, air, and solid surfaces.
At suitable concentrations, Potassium Stearate can form micelles, lamellar phases, gels, and other organized surfactant structures.

These structures are responsible for its cleansing, emulsifying, foaming, thickening, and lubricating behavior.
Potassium Stearate is commonly manufactured by neutralizing purified stearic acid with potassium hydroxide.

The neutralization process converts stearic acid into its potassium carboxylate salt and generates water as a reaction product.
Potassium Stearate may alternatively be produced through the saponification of stearin-rich fats or oils with potassium hydroxide.

When natural fatty-acid feedstocks are used, commercial material may contain potassium palmitate and smaller quantities of related fatty-acid salts.
Commercial specifications should therefore be reviewed carefully when a formulation requires chemically pure Potassium Stearate.

Potassium Stearate is generally supplied as a white to almost white powder, crystalline powder, granule, flake, or solid soap material.
Potassium Stearate is hygroscopic and can absorb atmospheric moisture during storage and handling.

Potassium Stearate's physical form, apparent density, water behavior, and processing characteristics depend on purity, particle size, moisture content, and fatty-acid distribution.
Compared with stearates of calcium, magnesium, or zinc, Potassium Stearate possesses substantially greater affinity for water.

Nevertheless, its long C18 chain limits rapid dissolution in cold water, particularly at high concentrations or in the presence of hardness ions.
Heating, agitation, alkaline conditions, and compatible co-surfactants generally improve hydration and dispersion.

Potassium Stearate may form translucent solutions, colloidal dispersions, gels, or opaque soap phases depending on concentration and temperature.
Hard-water ions such as calcium and magnesium can react with stearate ions to form less-soluble metallic soaps.

This reaction may reduce foam, create deposits, or destabilize formulations prepared with untreated hard water.
Acidification converts the stearate ion back into poorly water-soluble stearic acid.

For this reason, strongly acidic ingredients can reduce surfactant performance and cause precipitation.
Potassium Stearate generally produces an alkaline response when dispersed or dissolved in water.

The exact pH depends on concentration, residual alkalinity, free fatty acid content, purity, and the analytical method employed.
In cosmetic emulsions, Potassium Stearate can be generated in situ by neutralizing stearic acid with potassium hydroxide during manufacture.

In-situ formation allows formulators to control the relationship between unneutralized stearic acid and the resulting potassium soap.
This balance influences emulsion stability, foam, viscosity, skin feel, cleansing strength, and final product appearance.

Potassium Stearate produces softer and more water-compatible soap systems than sodium stearate, which is useful in shaving creams and soft soaps.
Potassium Stearate's long hydrocarbon chain contributes creamy foam, lubricity, and structural body rather than the very rapid foam associated with shorter-chain soaps.

Potassium Stearate remains chemically stable under ordinary dry storage conditions but can gradually absorb water or carbon dioxide from the atmosphere.
Exposure to excessive heat may cause discoloration, degradation, or decomposition rather than clean volatilization.

Combustion or thermal decomposition can generate carbon oxides, potassium-containing residues, smoke, and irritating decomposition products.

Potassium Stearate should be selected according to the intended regulatory market because cosmetic, pharmaceutical, food, laboratory, and industrial grades may have different purity and contaminant specifications.

PROPERTIES

Chemical Name: Potassium Stearate

IUPAC Name: Potassium Octadecanoate

INCI Name: Potassium Stearate

Chemical Class: Potassium fatty-acid salt

Substance Type: Long-chain anionic surfactant and potassium soap

CAS Number: 593-29-3

EC Number: 209-786-1

CosIng Reference Number: 37027

UNII: 17V812XK50

MDL Number: MFCD00072385

Molecular Formula: C₁₈H₃₅KO₂

Linear Formula: C₁₈H₃₅O₂K

Molecular Weight: 322.57 g/mol

InChIKey: ANBFRLKBEIFNQU-UHFFFAOYSA-M

Physical State at 20°C: Solid

Appearance: White to almost white powder or crystalline solid

Odor: Slight characteristic fatty or soap-like odor

Taste: Soap-like and alkaline

Purity: Grade-dependent; high-purity laboratory grades may be supplied at approximately 98%

Commercial Composition: May contain potassium palmitate and related fatty-acid salts

Surfactant Type: Anionic

Ionic Character: Potassium carboxylate salt

Hydrophobic Group: Linear C18 hydrocarbon chain

Hydrophilic Group: Potassium carboxylate

Primary Functions: Cleansing, emulsifying, surfactant, foaming, and lubricating agent

Water Behavior: Hydratable and dispersible; solubility increases with heat, agitation, alkalinity, and suitable co-surfactants

Cold-Water Behavior: Limited or slow dissolution depending on concentration and grade

Hot-Water Behavior: More readily dispersed or dissolved than in cold water

Oil Solubility: Generally insoluble in non-polar oils

Aqueous Reaction: Alkaline

Hygroscopicity: Hygroscopic

Melting and Thermal Behavior: Grade-dependent; decomposes or undergoes chemical change at elevated temperature

Volatility: Negligible under normal conditions

Vapor Pressure: Negligible

Foaming Ability: Produces stable, creamy soap foam in suitable formulations

Emulsifying Ability: Effective in compatible oil-in-water and soap-based systems

Hard-Water Compatibility: Reduced by calcium and magnesium ions

Acid Stability: Incompatible with strong acids because stearic acid may precipitate

Alkali Compatibility: Generally compatible with alkaline soap systems

Oxidation Stability: Stable under ordinary recommended storage conditions

Combustibility: Organic solid capable of burning under suitable fire conditions

Storage Condition: Cool, dry, and well-ventilated area

Moisture Protection: Keep tightly closed and protect from humidity

Recommended Laboratory Storage: Ambient or cool storage according to supplier instructions

Some commercial TCI material is specified as a white to almost white hygroscopic solid containing potassium palmitate, whereas high-purity supplier grades are identified as solid Potassium Stearate with a molecular weight of 322.57 g/mol.

FIRST AID

Inhalation: Move the affected person to fresh air and keep the individual at rest in a position comfortable for breathing. Avoid further exposure to airborne powder or aerosol. Obtain medical attention if coughing, throat irritation, respiratory discomfort, or breathing difficulty develops or persists.

Skin Contact: Remove contaminated clothing and rinse the affected skin immediately with plenty of water. Wash thoroughly with mild soap and water while avoiding vigorous rubbing. Because concentrated or high-purity grades may produce significant alkaline irritation or corrosive effects, obtain medical advice if pain, redness, blistering, or persistent irritation occurs.

Eye Contact: Immediately rinse the eyes cautiously with clean running water for at least 15 minutes while holding the eyelids apart. Remove contact lenses when present and easy to do, then continue rinsing. Do not allow the affected person to rub the eyes. Seek prompt medical attention because concentrated dust or alkaline solutions may cause serious eye injury.

Ingestion: Rinse the mouth thoroughly with water. Do not induce vomiting unless specifically instructed by qualified medical personnel. Never give anything by mouth to an unconscious person. Contact a physician or poison information center if a significant quantity has been swallowed or if pain, nausea, vomiting, or other symptoms occur.

Note to Physicians: Treat symptomatically and provide supportive care. Consider the alkaline soap character of the material and the possibility of irritation or corrosive injury from concentrated product. The hazard classification can vary with purity and commercial composition, so the current supplier-specific Safety Data Sheet should be reviewed.

HANDLING AND STORAGE

Handling: Handle Potassium Stearate in accordance with good industrial hygiene and chemical-processing practices. Avoid inhaling dust, generating unnecessary airborne particles, and allowing the product to contact the eyes or skin. Use clean, dry equipment and keep containers closed when material is not being transferred. Avoid contamination with acids, oxidizing agents, and multivalent metal salts unless the reaction is intentional.

Ventilation: Provide adequate general ventilation during routine handling. Local exhaust ventilation should be installed at bag opening, weighing, powder charging, milling, or mixing points where dust may become airborne. Use suitable respiratory protection when engineering controls cannot maintain exposure at an acceptable level.

Storage: Store in tightly sealed original containers in a cool, dry, and well-ventilated location. Protect the product from moisture, high humidity, direct sunlight, excessive heat, and contamination. Keep away from strong acids, strong oxidizing agents, and incompatible reactive chemicals. Follow the storage temperature specified by the individual supplier, as recommendations vary by grade.

Spill and Leak Procedures: Restrict access to the affected area and avoid generating airborne dust. Collect dry material using a suitable industrial vacuum or a low-dust mechanical method. Do not use compressed air for cleanup. Prevent large quantities from entering drains because the product may produce foam, increase alkalinity, and interfere with wastewater systems. Place recovered material in clean, labeled containers for reuse or disposal according to local requirements.

Handling Precautions: Wear appropriate chemical-resistant gloves, safety goggles or a face shield, protective clothing, and respiratory protection when required by the workplace assessment. Wash thoroughly after handling and before eating, drinking, or smoking. Keep emergency eyewash and washing facilities accessible. Because supplier classifications differ by purity and formulation, consult the current product-specific Safety Data Sheet before commercial use.