Poloxamer 338

What is Poloxamer 338?

Poloxamer 338 is a synthetic, nonionic block copolymer made from polyethylene oxide and polypropylene oxide units, resulting in a high molecular weight polymer with amphiphilic properties. This structure allows it to function effectively in rinse-off cosmetic products such as shampoos, body washes, facial cleansers, and micellar waters. It works by reducing surface tension at the interface between water, oil, and skin, forming micelles that encapsulate and lift away soils, sebum, and residues for easy rinsing. In formulations, it also acts as an emulsifier to blend oil and water phases stably and as a solubilizer for hydrophobic ingredients like fragrances. Its large molecular size limits skin absorption, contributing to its profile in personal care items focused on cleansing and delivery.

Comedogenic Rating 0/5 Low risk of clogging pores
EWG Safety Rating 2 View on EWG →
PubChem View on PubChem →

Roles in Formulation

This ingredient serves the following purposes in cosmetic formulations:

Surfactant
Lowers surface tension to enable cleansing, emulsifying, and foaming; central to shampoos, body washes, and many emulsions and micellar systems.
Cleansing agent
Removes dirt, oil, and impurities by lowering surface tension and forming micelles, enabling soils to be lifted and rinsed away from skin, hair, or teeth.

Benefits

Provides effective yet gentle cleansing by trapping oils and impurities in micelles.

Supports stable emulsions in multi-phase products like cleansers and shampoos.

Facilitates foaming and rinsing for a clean feel without residue.

Who It's For

A quick guide for who this ingredient may suit (and who should be cautious).

Who May Benefit Who Should Avoid
Individuals with normal to oily skin seeking thorough yet mild cleansing.
Those with sensitivity to nonionic surfactants.
Users of daily rinse-off products like body washes or shampoos.
Individuals preferring anhydrous or surfactant-free products.
People preferring non-comedogenic surfactants in their routines.
People with very dry skin opting for cream-based cleansers.

Safety Notes

  • Considered safe for cosmetic use by expert reviews like CIR.
  • Low comedogenic potential, suitable for acne-prone skin.

Frequently Asked Questions about Poloxamer 338

What does Poloxamer 338 do in products?

It lowers surface tension to cleanse by forming micelles that lift dirt and oil, and stabilizes emulsions.

Is Poloxamer 338 safe for sensitive skin?

It has a low irritation profile in rinse-off products per cosmetic safety assessments.

Does it clog pores?

Rated non-comedogenic, making it suitable for routine cleansing without pore concerns.