What Is C4-24 Alkyl Dimethicone/Divinyldimethicone Crosspolymer?
C4-24 Alkyl Dimethicone/Divinyldimethicone Crosspolymer is a silicone based copolymer created by crosslinking short to mid length C4-C24 alkyl dimethicone chains with divinyldimethicone. The resulting three-dimensional network behaves like a flexible mesh that sits on the skin. Silicones of this type first gained traction in the late 1990s when formulators were looking for lighter, longer-lasting alternatives to heavier oils. Advances in silicone chemistry allowed manufacturers to attach various alkyl groups and then lock them in place through a crosslinking reaction, giving this ingredient its unique feel and performance.
Production starts with dimethicone molecules that have been modified with alkyl groups ranging in length from four to twenty-four carbons. These molecules are mixed with divinyldimethicone and a catalyst, then heated so the vinyl groups react and form a crosslinked network. The finished material is usually delivered as a fine powder or pre-dispersed in a volatile carrier fluid, ready to be blended into formulas at the cooling stage.
You will most often find C4-24 Alkyl Dimethicone/Divinyldimethicone Crosspolymer in primers, liquid and cream foundations, tinted moisturizers, mattifying sunscreens, leave-on masks, anti-aging serums and long-wear lip or eye products. Its silky glide and soft-focus finish make it popular in color cosmetics while its film forming ability helps skin care products stay put longer.
C4-24 Alkyl Dimethicone/Divinyldimethicone Crosspolymer’s Cosmetic Benefits/Uses
This multifunctional silicone brings several practical advantages to modern beauty formulas:
- Film forming – Creates an invisible breathable layer that locks in moisture, improves product wear time and provides a smooth even finish on the skin
- Skin conditioning – Leaves a soft velvety touch, reduces the look of fine lines and gives an immediate silky after-feel without greasiness
- Viscosity controlling – Thickens oil or silicone phases which helps stabilize emulsions, suspend pigments and deliver a creamy yet lightweight texture
Who Can Use C4-24 Alkyl Dimethicone/Divinyldimethicone Crosspolymer
This silicone mesh suits almost every skin type, including oily, combination, dry, mature and sensitive skin, because it feels weightless and allows water vapor to pass through while still holding moisture in. Those with very clogged pore prone or silicone sensitive skin should keep an eye on how their skin reacts, but most users in these groups still tolerate it well since it has a low occlusion profile.
The material is fully synthetic and contains no animal derived components, so it fits vegan and vegetarian lifestyles.
Current data show no reproductive or developmental concerns for topical use. Pregnant or breastfeeding women can generally use products containing this polymer, though this is not medical advice and anyone who is expecting or nursing should review their routine with a physician just to be safe.
C4-24 Alkyl Dimethicone/Divinyldimethicone Crosspolymer does not absorb UV light and does not make skin more sensitive to the sun, so it carries no known risk of photosensitivity.
Potential Side Effects/Adverse Reactions
Responses to any cosmetic ingredient differ from one person to another. The effects listed below are possible yet uncommon when the polymer is formulated and used correctly, and most people will never encounter them.
- Mild redness or itching due to individual intolerance to silicones
- Transient breakouts if the breathable film traps excess sebum or debris on highly acne prone skin
- Stinging or watering eyes if a powder or fluid containing the polymer migrates into the eye area
- Enhanced irritation from other actives because the film can hold potent ingredients closer to the skin for longer periods
If you experience any discomfort or unexpected reaction stop using the product and seek advice from a healthcare professional.
Comedogenic Rating
Rating: 1/5. The crosslinked silicone network sits lightly on skin, allows water vapor to escape and does not mix with sebum, so it is unlikely to clog pores. Unlike heavier oils or waxes its molecules are too large and too structured to penetrate follicular openings, which keeps the risk of comedones low.
Most people who are prone to acne or breakouts can use products containing this polymer without issues.
That said, any formula can become more or less pore clogging depending on the other ingredients, the amount used and cleansing habits, so always consider the full product rather than a single component.
Summary
C4-24 Alkyl Dimethicone/Divinyldimethicone Crosspolymer is valued for three main jobs: it forms a breathable film that boosts wear time and locks in moisture, conditions skin with a silky soft finish and stabilizes texture by thickening the oil or silicone phase. It does all this thanks to its three dimensional silicone mesh that spreads smoothly yet stays in place once the volatile carriers evaporate.
The ingredient is fairly popular in primers, long wear foundations, matte sunscreens and lightweight serums, though less common in budget lines where simpler silicones dominate.
Current research shows it is safe for topical use, non sensitizing and free of major health concerns. As with any cosmetic ingredient it is smart to patch test a new product first just to make sure your skin plays nicely with the full formula.