What Is Polyurea Crosspolymer-8?
Polyurea Crosspolymer-8 is a crosslinked synthetic polymer created through a multi-step reaction that starts with toluene diisocyanate, trimethylolpropane and diethylene glycol. These building blocks first form a polyurethane-type backbone. The intermediate is then treated with hydrazine hydrate and guanidine carbonate, transforming the chains into a highly branched polyurea network. The result is an ultra-fine porous powder that feels silky when rubbed between the fingers.
Although polyurea chemistry has been used in industrial coatings since the late 1980s, cosmetic scientists adopted the technology much later when they discovered that certain crosslinked versions could form flexible films on skin without the tacky feel associated with older film formers. Polyurea Crosspolymer-8 was developed to meet this need and gained traction in color cosmetics and skin care around the mid-2010s.
Manufacturing involves carefully controlled temperature and pH conditions to ensure the right degree of crosslinking, followed by milling and sieving to obtain uniform particle size. Because it is produced in powder form it disperses easily in both water-based and anhydrous formulas, giving chemists freedom to use it in many product types.
You will most often find Polyurea Crosspolymer-8 in primers, foundations, long-wear concealers, setting sprays, facial masks, anti-aging serums, sunscreens and certain hair styling products where a lightweight flexible film is desirable.
Polyurea Crosspolymer-8’s Cosmetic Benefits/Uses
In topical products Polyurea Crosspolymer-8 serves a single yet valuable role.
As a film forming agent it creates an invisible breathable layer on skin or hair that helps lock in moisture, improve spreadability and boost wear time of pigments or active ingredients. The flexible film resists cracking so makeup stays smooth longer and skincare benefits remain in contact with the surface for extended efficacy.
Who Can Use Polyurea Crosspolymer-8
Because it forms a light flexible film without clogging pores Polyurea Crosspolymer-8 is generally well tolerated by oily, combination, normal and dry skin types. Most sensitive skin users also get along with it since the polymer is inert and has no fragrance or preservatives of its own, though highly reactive skin could still experience redness if a formula contains other trigger ingredients.
The material is 100 percent synthetic and contains no animal derived components so it is considered suitable for both vegans and vegetarians.
No absorption into the bloodstream has been shown for this large polymer and regulators have not flagged it as a reproductive toxin. Pregnant or breastfeeding individuals can usually use products containing Polyurea Crosspolymer-8, yet this is not medical advice and anyone expecting or nursing should clear all skincare products with a qualified health professional first to be safe.
The ingredient does not cause photosensitivity and has no known conflicts with typical actives such as retinoids, vitamin C or exfoliating acids.
Potential Side Effects/Adverse Reactions
Responses to topical Polyurea Crosspolymer-8 vary from person to person. The points below outline potential issues only. When the ingredient is properly formulated most users will not notice any of these reactions.
- Mild skin irritation
- Transient redness or warmth in very sensitive skin
- Contact dermatitis in individuals allergic to isocyanate residues
- Eye irritation if loose powder or product mist gets into the eyes
- Occlusive sensation when applied too thickly on very oily skin
If any adverse effect occurs stop use immediately and seek guidance from a healthcare professional.
Comedogenic Rating
Rating: 1 out of 5
Polyurea Crosspolymer-8 is a large, crosslinked polymer that stays on the surface rather than sinking into pores. It contains no oils or waxes that could feed acne-causing bacteria and the breathable film it forms lets sebum escape, which keeps congestion risk low. A tiny chance of pore blockage exists if a very thick layer is applied on extremely oily skin, so it does not quite earn a perfect zero.
Suitable for acne-prone and breakout-prone skin in most cases.
As with any film former, how comedogenic the final product feels also depends on the other ingredients, so check the full formula if you are highly sensitive.
Summary
Polyurea Crosspolymer-8 is used in cosmetics as a lightweight film former that locks moisture in, improves spreadability and extends wear time for pigments or actives. It achieves these benefits by creating an invisible flexible network on the skin or hair surface that moves with facial expressions and resists cracking.
The ingredient is moderately popular in long-wear makeup, primers and certain skincare products, yet it remains a niche choice compared with silicone elastomers or traditional acrylates because it is newer and slightly costlier.
Current data show Polyurea Crosspolymer-8 is low risk for irritation, virtually non-comedogenic and safe for all skin types when used as directed. Still, everyone’s skin is unique so perform a small patch test when trying any new product that contains this polymer to be on the safe side.