What Is Polyacrylate Crosspolymer-4?
Polyacrylate Crosspolymer-4 is a man-made polymer created by linking together several small building-block chemicals, including sodium acryloyldimethyltaurate, dimethyl acrylamide, sodium acrylate, acrylic acid and hydroxyethylacrylate, then crosslinking them with methylene bis-propenamide. The end result is a large, mesh-like molecule that swells in water and can trap oils, giving it useful thickening and stabilising qualities.
The material traces its roots to the wider family of acrylate polymers that started appearing in personal care during the 1970s as safer, more efficient alternatives to natural gums. Over the years chemists tweaked the recipe to improve clarity, salt tolerance and skin feel, eventually arriving at the version known as Polyacrylate Crosspolymer-4.
Production begins with a water-based solution where each monomer is combined in precise ratios. A catalyst is added to kick off polymerisation, turning the liquid into a soft gel. The gel is dried, ground into a fine powder, then carefully sieved to ensure uniform particle size. When this powder is blended into a cosmetic formula and exposed to water it re-hydrates, instantly thickening the mixture and locking oil and water together.
You’ll most often find Polyacrylate Crosspolymer-4 in lightweight moisturisers, hydrating gels, sheet mask essences, sunscreen lotions, colour cosmetics like BB creams and foundations, as well as hair styling products that need a clear non-sticky hold.
Polyacrylate Crosspolymer-4’s Cosmetic Benefits/Uses
In beauty formulas Polyacrylate Crosspolymer-4 does a few key jobs that boost both texture and performance
- Emulsion stabilising: Keeps water and oil phases from separating so creams stay smooth and uniform during shelf life and use
- Film forming: Leaves a thin flexible layer on skin or hair that helps lock in moisture, enhance spreadability and improve wear time of makeup or sunscreen
- Viscosity controlling: Provides quick thickening even in low concentrations letting formulators create everything from light gels to rich creams without heaviness
Who Can Use Polyacrylate Crosspolymer-4
Because it is a lightweight inert polymer, Polyacrylate Crosspolymer-4 is generally suitable for all skin types including oily, dry, combination and sensitive skin. It does not add oil or alcohol, it has no fragrance and it shows a very low irritation potential so even reactive complexions tend to tolerate it well.
The ingredient is entirely synthetic and contains no animal derived raw materials which makes it appropriate for both vegetarians and vegans.
Current safety data finds no specific risks for women who are pregnant or breastfeeding when Polyacrylate Crosspolymer-4 is applied to intact skin. This information is not medical advice; anyone who is expecting or nursing should show the full product label to a health professional before adding a new cosmetic to their routine just to be safe.
The polymer does not increase photosensitivity so it will not make skin more prone to sunburn. It is also odorless and compatible with most other skincare actives which means it rarely clashes with common ingredients used alongside it.
Potential Side Effects/Adverse Reactions
Individual responses to topical Polyacrylate Crosspolymer-4 can differ. The issues listed below are potential outcomes only and are not expected for the average user when the ingredient is formulated and used correctly.
- Mild skin irritation such as transient redness or itching
- Allergic contact dermatitis in users already sensitised to acrylates
- Temporary eye stinging if a product accidentally enters the eye area before it sets
- Very rare acne flare if used in an unusually heavy formula on acne-prone skin
If any discomfort or adverse change in the skin appears stop using the product and seek guidance from a qualified healthcare provider or dermatologist.
Comedogenic Rating
Rating: 0/5 (non-comedogenic)
Polyacrylate Crosspolymer-4 is a large water-swellable molecule that stays on the skin surface and contains no oils or waxes that can block pores. Because it does not penetrate or leave an occlusive film it earns the lowest possible comedogenic score.
That makes it generally suitable for acne-prone or breakout-prone skin.
One extra note: if the overall formula pairs this polymer with heavy oils or butters the final product could still clog pores, so always look at the full ingredient list not just one component.
Summary
Polyacrylate Crosspolymer-4 acts as an emulsion stabiliser, film former and viscosity controller. It swells in water to thicken a formula, its mesh structure keeps oil and water mixed, and once applied it dries to a light flexible film that holds moisture and improves wear time.
The polymer is a backstage workhorse rather than a headline ingredient. You will see it in many modern gels, lotions and sunscreens because it is reliable, easy to use and gives a clean skin feel even though it rarely gets talked about on product labels.
Current research shows a very low risk of irritation or pore clogging, and it is considered safe for all skin types when used as directed. As with any new cosmetic it is smart to patch test first to be sure your skin agrees with the complete formula.