Ingredient dictionary

PEG-55 Propylene Glycol Oleate

A nonionic surfactant, a cleansing molecule with no electrical charge, that helps oil and water blend together. It is on the label of 18 products in our library. Checked against our library November 6, 2026.

What PEG-55 Propylene Glycol Oleate does

Helps oil and water blend
Lifts oil and dirt from skin and hair
Keeps formulas smooth and stable

PEG-55 Propylene Glycol Oleate is made by linking a polyethylene glycol chain to propylene glycol and then to oleic acid. Oleic acid is a fatty acid found in many plant oils, such as olive oil. The number 55 refers to the average number of repeating units in the polyethylene glycol chain.

The molecule has two ends with different tastes. One end likes water, and the other likes oil, so it sits between them and helps them blend. Formulators use it in shampoos and cleansers to help oily ingredients and fragrance stay mixed in. It is a nonionic surfactant, meaning it has no electrical charge, which is one reason it often shows up in mild cleansers.

Good for

Well suited to shampoos and cleansers, where it helps oil and dirt rinse away while keeping formulas smooth.

Frequently asked questions

Is PEG-55 Propylene Glycol Oleate safe?

It is common in rinse-off products and is generally well tolerated. Like any surfactant, it can feel drying or irritating for some people, especially with sensitive skin. If you notice stinging or redness, stop using the product and check with a dermatologist.

Why does the PEG in the name matter?

PEG stands for polyethylene glycol, a common building block in cosmetics. Ethoxylated ingredients like this one can carry tiny trace byproducts from manufacturing. Reputable suppliers purify them, and careful manufacturing aims to keep those traces very low.