Propylene Glycol Isostearate

Benefits
MoisturizingSoftening

What is Propylene Glycol Isostearate?

Propylene Glycol Isostearate is a synthetic ester formed by combining propylene glycol, a simple alcohol derived from petroleum or plant sources, with isostearic acid, a branched-chain fatty acid produced by rearranging natural stearic acid from vegetable oils. This ingredient falls into the glycol ester family, widely incorporated into skincare products like lotions, creams, and cleansers. In formulations, it functions primarily as an emollient by depositing a thin lubricating layer on the skin to enhance smoothness and reduce friction. Its emulsifying action bridges oil and water components, promoting uniform blends and preventing separation. Additionally, surfactant properties lower surface tension, aiding dispersion and mild cleansing without harshness. The branched isostearate chain contributes to better solubility and oxidative stability over linear alternatives, making it suitable for various emulsion-based cosmetics.

Comedogenic Rating 0/5 Low risk of clogging pores
EWG Safety Rating 1 View on EWG →

Roles in Formulation

This ingredient serves the following purposes in cosmetic formulations:

Emollient
Softens and smooths skin by filling in surface roughness and improving slip; can also help reduce moisture loss when paired with occlusives and film formers.
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.
Skin conditioning agent
Maintains skin softness, smoothness, and flexibility.

Benefits

Supports skin moisturizing by helping retain hydration on the surface.

Promotes softening and smoother texture through emollient action.

Improves product feel and stability as an emulsifying agent.

Who It's For

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

Who May Benefit Who Should Avoid
People with dry skin needing added softness and hydration support.
Those with oily skin due to potential emollient buildup.
Individuals using lotions or creams for better texture and spread.
People preferring lightweight, non-occlusive formulas.
Users seeking mild surfactants in gentle cleansers.
Individuals sensitive to glycol-based ingredients.

Safety Notes

  • Earned a low hazard score of 1 from EWG assessments.
  • Considered non-comedogenic with a rating of 0.

Frequently Asked Questions about Propylene Glycol Isostearate

Is Propylene Glycol Isostearate comedogenic?

No, it has a comedogenic rating of 0, suitable for most skin types except oily.

What EWG rating does it have?

EWG scores it 1 across min and max, indicating low concern.

Can it moisturize skin?

Yes, it supports moisturizing and softening effects through emollient properties.