PEG-8 Isostearate

PEG / Ethoxylated

What is PEG-8 Isostearate?

PEG-8 Isostearate is a synthetic ethoxylated ester formed by combining isostearic acid—a branched-chain fatty acid derived from the isomerization of oleic acid in vegetable oils—with eight units of polyethylene glycol. This creates a hydrophilic molecule with lipophilic properties, placing it in the surfactant-emulsifier family for cosmetics. It appears in categories like facial cleansers, body washes, shampoos, lotions, and makeup removers. Functionally, it reduces surface tension at interfaces, enabling micelles to encapsulate and lift away oils, sebum, and residues during rinsing. In emulsions, it forms a protective film around droplets, promoting blend stability and preventing phase separation for even application and absorption. Its branched structure provides fluidity without greasiness, supporting clear, lightweight formulas across rinse-off and leave-on uses.

Comedogenic Rating 0/5 Low risk of clogging pores
EWG Safety Rating 3 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.
Emulsifying agent
Enables stable mixing of oil and water phases by forming an interfacial film, helping create lotions, creams, and cleansers with consistent texture.

Benefits

Supports thorough cleansing by dispersing dirt and oils for rinse-away.

Helps form stable lotions and creams with smooth, consistent feel.

Non-comedogenic profile suits clearer pore maintenance.

Who It's For

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

Who May Benefit Who Should Avoid
Users of cleansers needing effective impurity removal.
Those sensitive to ethoxylated compounds.
People with oily skin preferring lightweight emulsions.
People preferring PEG-free formulations.
Individuals seeking stable, non-separating moisturizers.
Users with allergies to fatty acid derivatives.

Safety Notes

  • Expert reviews deem it safe in typical cosmetic amounts.
  • Rated low comedogenic potential, unlikely to block pores.

Frequently Asked Questions about PEG-8 Isostearate

What does PEG-8 Isostearate do in products?

It acts as a surfactant to cleanse and an emulsifier to blend oils and water stably.

Is it suitable for acne-prone skin?

With a comedogenic rating of 0, it poses low risk of pore clogging.

Are there irritation concerns?

Evidence indicates low irritation potential in cosmetic applications.