What Is Pei-30?
Pei-30 is the cosmetic trade name for a homopolymer of aziridine, a small nitrogen-containing ring molecule that can link together to form long, flexible chains. Because it is synthesized in controlled laboratory settings, there is no plant or animal source involved; its origin lies in petrochemical feedstocks that are refined and reacted to create aziridine, which is then polymerized into Pei-30. The polymer first appeared in industrial applications as a paper and textile additive for its thickening ability, and formulators soon noticed that the same property could help stabilize personal care products. Production involves catalytic polymerization where individual aziridine units open and connect, forming a water-soluble polymer that can be purified and standardized for cosmetic use.
Today Pei-30 is most often tucked into formulas that need a silky yet stable texture. You will find it in sheet mask serums, hydrating gels, lightweight moisturizers, peel-off masks, micellar water cleansers and even some hair styling creams where it fine-tunes flow without weighing hair down.
Pei-30’s Cosmetic Benefits/Uses
Pei-30 plays one core role in cosmetics, acting as a viscosity controller that improves both the feel and performance of a wide range of products.
As a viscosity controlling agent, Pei-30 adjusts thickness so a formula is neither runny nor overly stiff. This helps suspend active ingredients evenly, prevents separation during storage, allows smooth spreading on skin and delivers a pleasant, non-sticky finish. The polymer forms a network that holds water and oils in balance, letting formulators create clear gels or creamy lotions without heavy waxes. The result is a product that feels elegant, stays stable through shelf life and rinses clean when desired.
Who Can Use Pei-30
Because Pei-30 mainly acts as a texture helper rather than an active treatment it is generally suitable for all skin types including dry, oily, combination and sensitive skin. It does not clog pores or leave a heavy film so acne-prone users usually tolerate it well. People with very reactive skin should still keep an eye on any new product but Pei-30 itself is considered low risk.
The polymer is made entirely in the lab from petrochemical feedstocks and contains no animal derivatives, making it acceptable for both vegans and vegetarians.
Current safety data show no specific hazards for pregnant or breastfeeding women when Pei-30 is applied topically in the small amounts found in finished cosmetics. This is not medical advice so anyone expecting or nursing should check with a healthcare provider before adding new products to their routine.
Pei-30 does not increase photosensitivity, meaning it will not make skin more prone to sunburn. Standard daily sun protection is still recommended for overall skin health.
Potential Side Effects/Adverse Reactions
Reactions to topical Pei-30 can vary from person to person. The effects listed below are possible but uncommon when the ingredient is used at the levels allowed in cosmetics.
- Mild skin irritation
- Temporary redness at the application site
- Stinging sensation on very sensitive or broken skin
- Rare allergic contact dermatitis in users already allergic to amine-based polymers
If you experience any of the above effects stop using the product and consult a healthcare professional for guidance.
Comedogenic Rating
Rating: 0/5
Pei-30 is a water-soluble polymer that does not form an oily or waxy film on the skin, so it has virtually no tendency to block pores. Its main job is to control thickness, not to sit on the surface or mix with sebum, which is why formulators consider it non-comedogenic.
That makes Pei-30 a safe pick for people who are prone to acne or breakouts.
As with any ingredient, the full formula matters. If Pei-30 is paired with heavy oils or butters, pore-clogging potential comes from those other ingredients, not the polymer itself.
Summary
Pei-30 is a lab made polymer that fine-tunes viscosity, keeps water and oils evenly mixed and gives products a smooth glide. It works by creating a light network in the formula that traps liquid, stops separation and helps active ingredients spread in a thin even layer.
You will not see Pei-30 called out in ad copy, yet it quietly shows up in many serums, gels and hair creams because it solves texture issues without adding weight. It is more of a behind-the-scenes helper than a headline star.
Current safety data say Pei-30 is low risk for skin and the environment when used at normal cosmetic levels. Still, every skin is different, so doing a small patch test with any new product is the easiest way to stay on the safe side.