Ingredient review
Bis-HEMA Poloxamer 251/IPDI Copolymer
INCI: BIS-HEMA POLOXAMER 251/IPDI COPOLYMER
A synthetic film-former that helps makeup and sunscreen stay put longer, but it may feel tight or heavy on very dry skin.
In plain English
This is a man-made polymer that forms a flexible, invisible film on your skin. It helps makeup resist sweat, water, and rubbing, so your foundation or mascara lasts longer. Think of it like a clear, breathable plastic wrap that holds ingredients in place.
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
Bis-HEMA Poloxamer 251/IPDI Copolymer 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 Bis-HEMA Poloxamer 251/IPDI Copolymer.
- 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 copolymer created by reacting bis-HEMA (a methacrylate monomer) with poloxamer 251 and IPDI (isophorone diisocyanate). It is designed to form a durable, flexible film on skin or hair.
How it works
When applied, the copolymer dries into a thin, continuous film that physically locks in pigments and active ingredients. This film is water-resistant and flexible, so it moves with your skin without cracking or flaking.
Pros
Long-lasting wear
Helps makeup and sunscreen stay intact for hours, even in humid or sweaty conditions.
Water resistance
Forms a barrier that resists water and sweat, making it ideal for waterproof formulas.
Cons and cautions
Potential tightness
On very dry skin, the film can feel tight or uncomfortable, especially if layered over drying ingredients.
Removal difficulty
Requires an oil-based or dual-phase cleanser to fully remove; water-only washing may leave residue.
Best for
- People who want long-wearing foundation or concealer
- Those who need water-resistant sunscreen for outdoor activities
Use caution if
- Individuals with very dry or dehydrated skin who dislike a tight feel
- Those who prefer minimalist or 'clean' ingredient lists
Usage tips
Safety summary
Generally recognized as safe for topical use at typical concentrations. Low irritation and comedogenic risk. No known systemic toxicity from dermal exposure.
Research notes
Safety data is based on analog studies of similar polyurethane film-formers. No specific human or animal studies on this exact copolymer were found. Industry experience supports its safe use in cosmetics.
Common label clues
- Typical concentration
- 0.5% to 5% in leave-on products
- Regulatory status
- Approved for use in cosmetics in the EU, US, and other major markets. No specific restrictions beyond general cosmetic safety requirements.
- Common uses
- Long-wear foundations, Waterproof mascaras, Lip products, Sunscreens
- Environmental note
- As a synthetic polymer, its biodegradability is low. It may contribute to microplastic pollution if not filtered during wastewater treatment.
Good to know
- This ingredient is often listed near the end of an INCI because it is used at low concentrations.
- It is not considered a microplastic, but its environmental persistence is not fully studied.
Common questions
What is Bis-HEMA Poloxamer 251/IPDI Copolymer in beauty products?
This is a man-made polymer that forms a flexible, invisible film on your skin. It helps makeup resist sweat, water, and rubbing, so your foundation or mascara lasts longer. Think of it like a clear, breathable plastic wrap that holds ingredients in place.
What does Bis-HEMA Poloxamer 251/IPDI Copolymer do in a beauty product?
When applied, the copolymer dries into a thin, continuous film that physically locks in pigments and active ingredients. This film is water-resistant and flexible, so it moves with your skin without cracking or flaking.
Is Bis-HEMA Poloxamer 251/IPDI Copolymer safe for most people?
Generally recognized as safe for topical use at typical concentrations. Low irritation and comedogenic risk. No known systemic toxicity from dermal exposure.
Who should be careful with Bis-HEMA Poloxamer 251/IPDI Copolymer?
Individuals with very dry or dehydrated skin who dislike a tight feel Those who prefer minimalist or 'clean' ingredient lists
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.