Get a Free 5ml Mini Now Free 5ml Mini With Every Order of The Mantle

POLOXAMER 251.

Valuable / CLEANSING, SURFACTANT - CLEANSING

Poloxamer 251 is a non-ionic, amphiphilic copolymer engineered to act as a versatile surfactant. Composed of hydrophilic polyoxyethylene and hydrophobic polyoxypropylene blocks, it effectively emulsifies and solubilizes a range of substances in skincare formulations.

surfactant/cleansing emulsifying solubilizing

Science

This ingredient functions by significantly reducing the surface tension of liquids, facilitating their mixing. As an emulsifying agent, it stabilizes oil and water phases, preventing separation. Furthermore, as a solubilizing agent, it enables the uniform dispersion of oil-loving compounds within aqueous solutions. In cleansing applications, it helps water efficiently bind with oils and dirt, allowing for their easy removal from skin.


Research

Low confidence
Effective range N/A
Optimal

N/A


Transparency

Not commonly dusted

The Formula

Solubility
Both
Optimal pH ≥6
0 7 14

Stability

Poloxamer 251 exhibits amphiphilic properties, providing solubility in both water and the capacity to solubilize oil-soluble ingredients in water-based systems. It demonstrates 'reverse solubility,' showing enhanced solubility in colder water (5–10 °C). Stability can be compromised in highly acidic conditions, with degradation into formic and acetic acids observed at pH values below approximately 6.

Conflicts

  • May exhibit limitations in solubilizing very poorly soluble active pharmaceutical ingredients.
  • Strong acidic conditions (below pH 6) can lead to degradation.

Safety

CIR Status
Safe as used
Max tested
20%
Sensitization risk Low

The Cosmetic Ingredient Review (CIR) Expert Panel deemed poloxamers, including Poloxamer 251, safe for cosmetic use, with a maximum recommended concentration of 20%. While reproductive and developmental toxicity data were absent, the panel concluded that skin penetration should be minimal and slow due to its molecular weight and solubility. Emphasized is the critical importance of purification processes to ensure impurities like ethylene oxide, propylene oxide, and 1,4-dioxane remain below established limits. Poloxamers also hold FDA approval as pharmaceutical excipients.


Your Skin

Yes Normal
Yes Dry
Yes Oily
Yes Sensitive
Irritancy Low
Comedogenicity Low

Our Assessment

Valuable

Poloxamer 251 is a valuable surfactant, emulsifier, and solubilizer, highly compatible with all skin types and deemed safe for use in various formulations at concentrations up to 20%.


Related

Finding similar ingredients…