Ingredient review
PEG-100 Polycaprolactone Ethylhexanoate
INCI: METHOXY PEG-100/POLYEPSILON CAPROLACTONE ETHYLHEXANOATE
A synthetic polymer that helps products spread smoothly and feel lightweight, but its PEG component raises mild environmental and purity concerns.
In plain English
This ingredient is a man-made polymer (a long chain of repeating molecules) that helps cosmetic products spread easily on your skin and form a light, flexible film. It's often used to improve the feel of creams and sunscreens, making them less greasy. The 'PEG' part means it's processed with ethylene oxide, which can sometimes contain trace impurities, but cosmetic-grade versions are purified to be safe for use.
Review score
Safety, usefulness, and evidence
Potentially useful with some tradeoffs
The evidence base is useful, but some claims depend heavily on the formula.
Risk flags are low for most users, though the finished product can still irritate.
- Source
- synthetic
- Evidence
- moderate
- Irritation
- low
- Clogging risk
- low
Quick decision guide
Useful, but context matters
PEG-100 Polycaprolactone Ethylhexanoate is generally a lower-concern ingredient when the full formula suits your skin.
Plain-English read
Treat this as a practical screening step before you compare products that contain this ingredient.
- Step 1Start with the score, then check the irritation and clogging risk before judging PEG-100 Polycaprolactone Ethylhexanoate.
- Step 2Use the "Best for" and "Use caution if" sections to match the ingredient to your skin, not just to a marketing claim.
- Step 3If a product stings, breaks you out, or worsens irritation, judge the finished formula and stop using it even if the ingredient scores well.
Score terms in plain English
Irritation risk
lowLess likely to sting, burn, or bother most users, though sensitive skin can still react.
Clogging risk
lowLess likely to feel heavy or contribute to clogged pores for most skin types.
Evidence level
moderateThere is useful support, but formula details and claim strength still matter.
What it is
A synthetic polymer derived from polyethylene glycol (PEG) and caprolactone, chemically modified to be oil-soluble. It acts as a film former and texture enhancer.
How it works
When applied, it forms a thin, flexible film on the skin or hair that helps other ingredients stay in place and gives a smooth, silky feel. It also helps stabilize emulsions (mixtures of oil and water) so the product doesn't separate.
Pros
Lightweight feel
Creates a silky, non-greasy finish on skin, making it ideal for daytime moisturizers and sunscreens.
Improves wear time
Helps makeup and sunscreen ingredients stay in place longer, reducing the need for frequent reapplication.
Cons and cautions
Environmental persistence
As a synthetic polymer, it is not readily biodegradable and may accumulate in the environment over time.
Purity concerns
The PEG component can contain trace impurities like 1,4-dioxane if manufacturing standards are not strict, though reputable brands use purified grades.
Best for
- Anyone looking for lightweight, non-greasy moisturizers or sunscreens
- People who want makeup or SPF to stay put longer
Use caution if
- Those who prefer only biodegradable or natural ingredients
- Individuals with known sensitivity to PEG compounds (rare)
Usage tips
Safety summary
Generally safe for topical use at typical concentrations. The main concern is potential trace impurities from the PEG manufacturing process, which are minimized by reputable suppliers. The Cosmetic Ingredient Review panel has deemed it safe as used.
Research notes
Limited peer-reviewed studies specifically on this ingredient, but its components (PEGs and polycaprolactone) are well-studied and considered safe. The CIR panel reviewed similar PEG polymers and found them safe for cosmetic use.
Common label clues
- Typical concentration
- 0.5% to 5%
- Regulatory status
- Approved for use in cosmetics globally, including by the FDA (US) and EU CosIng database, with no specific concentration restrictions.
- Common uses
- Moisturizers, Sunscreens, Makeup, Hair products
- Environmental note
- As a synthetic polymer, it is not biodegradable and may contribute to microplastic pollution. Some regions are considering restrictions on non-biodegradable polymers in rinse-off products.
Good to know
- This ingredient is often used in combination with other film formers to enhance water resistance in sunscreens.
- It is considered safe by the Cosmetic Ingredient Review (CIR) panel at typical use levels.
Common questions
What is PEG-100 Polycaprolactone Ethylhexanoate in beauty products?
This ingredient is a man-made polymer (a long chain of repeating molecules) that helps cosmetic products spread easily on your skin and form a light, flexible film. It's often used to improve the feel of creams and sunscreens, making them less greasy. The 'PEG' part means it's processed with ethylene oxide, which can sometimes contain trace impurities, but cosmetic-grade versions are purified to be safe for use.
What does PEG-100 Polycaprolactone Ethylhexanoate do in a beauty product?
When applied, it forms a thin, flexible film on the skin or hair that helps other ingredients stay in place and gives a smooth, silky feel. It also helps stabilize emulsions (mixtures of oil and water) so the product doesn't separate.
Is PEG-100 Polycaprolactone Ethylhexanoate safe for most people?
Generally safe for topical use at typical concentrations. The main concern is potential trace impurities from the PEG manufacturing process, which are minimized by reputable suppliers. The Cosmetic Ingredient Review panel has deemed it safe as used.
Who should be careful with PEG-100 Polycaprolactone Ethylhexanoate?
Those who prefer only biodegradable or natural ingredients Individuals with known sensitivity to PEG compounds (rare)
Research sources
Ingredient reviews are educational and are not medical advice. Patch test new products and ask a licensed clinician about persistent irritation, allergies, pregnancy-specific questions, or diagnosed skin conditions.