Ingredient review
Glycerylamidoethyl Methacrylate/Stearyl Methacrylate Copolymer
INCI: GLYCERYLAMIDOETHYL METHACRYLATE/STEARYL METHACRYLATE COPOLYMER
A synthetic film-former that helps makeup and sunscreen stay put longer, especially in water or sweat.
In plain English
This ingredient is a type of plastic-like polymer that forms a thin, flexible film on your skin. It's added to products like sunscreen and waterproof makeup to help them resist water, sweat, and rubbing off. Think of it like a clear, invisible shield that keeps the product 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
Glycerylamidoethyl Methacrylate/Stearyl Methacrylate 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 Glycerylamidoethyl Methacrylate/Stearyl Methacrylate 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 made from two monomers: glycerylamidoethyl methacrylate and stearyl methacrylate. It is designed to create a durable, water-resistant film on the skin or hair.
How it works
When applied, the polymer molecules link together as the solvent (like water or alcohol) evaporates, forming a continuous film. This film physically blocks water and oil from breaking down the product, enhancing longevity and water resistance.
Pros
Strong water resistance
Helps sunscreen and makeup stay effective even when you sweat or swim, so you don't have to reapply as often.
Lightweight feel
Despite its durability, the film is thin and flexible, so it doesn't feel heavy or cakey on the skin.
Cons and cautions
Can be drying
The film may trap moisture less effectively, potentially leaving dry or sensitive skin feeling tight or parched.
Requires double cleansing
Because it's water-resistant, you'll likely need an oil-based cleanser or micellar water to remove it fully, adding a step to your routine.
Best for
- People who need long-lasting makeup or sunscreen
- Those who swim, sweat, or live in humid climates
Use caution if
- Individuals with very dry or compromised skin barriers who prefer minimal film-formers
Usage tips
Safety summary
Generally recognized as safe for topical cosmetic use. Low irritation and comedogenic potential. No significant safety concerns reported in standard use concentrations.
Research notes
Limited independent studies specific to this copolymer, but the broader class of methacrylate copolymers has been reviewed by the CIR and found safe. Evidence for efficacy in water resistance is supported by formulation science.
Common label clues
- Typical concentration
- 0.5% to 5%
- Regulatory status
- Approved for use in cosmetics in the US, EU, and many other regions. The Cosmetic Ingredient Review (CIR) panel has evaluated similar methacrylate copolymers and found them safe at typical use concentrations.
- Common uses
- Sunscreens, Waterproof makeup, Long-wear foundations, Mascaras
- Environmental note
- As a synthetic polymer, it is not biodegradable. However, it is used in small amounts and is not known to bioaccumulate significantly.
Good to know
- This polymer is often used in combination with other film-formers for enhanced durability.
- It is considered safe for use in cosmetics by major regulatory bodies.
Common questions
What is Glycerylamidoethyl Methacrylate/Stearyl Methacrylate Copolymer in beauty products?
This ingredient is a type of plastic-like polymer that forms a thin, flexible film on your skin. It's added to products like sunscreen and waterproof makeup to help them resist water, sweat, and rubbing off. Think of it like a clear, invisible shield that keeps the product in place.
What does Glycerylamidoethyl Methacrylate/Stearyl Methacrylate Copolymer do in a beauty product?
When applied, the polymer molecules link together as the solvent (like water or alcohol) evaporates, forming a continuous film. This film physically blocks water and oil from breaking down the product, enhancing longevity and water resistance.
Is Glycerylamidoethyl Methacrylate/Stearyl Methacrylate Copolymer safe for most people?
Generally recognized as safe for topical cosmetic use. Low irritation and comedogenic potential. No significant safety concerns reported in standard use concentrations.
Who should be careful with Glycerylamidoethyl Methacrylate/Stearyl Methacrylate Copolymer?
Individuals with very dry or compromised skin barriers who prefer minimal film-formers
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.