PEG-175 Diisostearate

What is PEG-175 Diisostearate?

PEG-175 Diisostearate is a polyethylene glycol (PEG) diester formed by reacting diisostearic acid—a branched, saturated fatty acid derived from oleic acid—with PEG containing an average of 175 ethylene oxide units. This creates a long-chain, water-soluble polymer commonly used in rinse-off and leave-on skincare products like body washes, moisturizers, and foundations. Its chemical structure enables it to act at the interface between oil and water, reducing interfacial tension to form stable emulsions that prevent separation. As a surfactant, it helps solubilize oils and enhance wetting properties during cleansing. The viscosity-controlling aspect allows formulators to fine-tune product consistency for optimal spreadability and feel on the skin.

Comedogenic Rating 0/5 Low risk of clogging pores
EWG Safety Rating 3 View on EWG →

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.
Emulsifying agent
Enables stable mixing of oil and water phases by forming an interfacial film, helping create lotions, creams, and cleansers with consistent texture.
Viscosity controlling agent
Adjusts thickness to the desired level for stability and usability, improving dispensing, suspension, and texture across many formulation types.

Benefits

Supports stable blending of oils and water for uniform product texture

Facilitates effective cleansing by dispersing oils and impurities

Allows customizable thickness for smooth application and dispensing

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 emulsion-based moisturizers and lotions
People sensitive to ethoxylated ingredients
Individuals incorporating foaming or micellar cleansers
Those wary of potential manufacturing impurities
Those preferring products with consistent, easy-to-apply consistency
Individuals seeking fragrance-free, minimalistic formulations

Safety Notes

  • Assessed as safe for cosmetic use by expert review panels
  • High-quality production minimizes risks from process impurities

Frequently Asked Questions about PEG-175 Diisostearate

What does PEG-175 Diisostearate do in products?

It emulsifies oil and water phases, aids cleansing as a surfactant, and adjusts viscosity for better texture.

Is PEG-175 Diisostearate comedogenic?

Rated 0 for comedogenicity, indicating low likelihood of pore-clogging.

What are common concerns with this ingredient?

Mainly potential impurities from ethoxylation, addressed in reputable manufacturing.