What Is Peg/Ppg-18/12 Dimethicone?
Peg/Ppg-18/12 Dimethicone is a silicone based ingredient created by attaching roughly 18 units of ethylene oxide and 12 units of propylene oxide to a dimethicone backbone. This hybrid structure gives the molecule both oil loving and water loving parts, letting it spread easily while also blending with water based formulas. The raw materials start with silica derived dimethicone, then go through a controlled alkoxylation process that adds the PEG and PPG chains. The result is a clear fluid that feels silky yet lightweight.
Silicones first entered cosmetics in the 1950s for their smooth feel and water resistance. Chemists soon looked for ways to make them more compatible with lotions and creams, leading to pegylated versions like Peg/Ppg-18/12 Dimethicone. Its balanced structure has been popular since the 1990s because it can improve texture without the heavy, greasy afterfeel often linked to older silicones.
You will most often see Peg/Ppg-18/12 Dimethicone in moisturizers, primers, serums, sunscreens, color cosmetics and hair smoothing products. It is valued for giving a soft finish, boosting spreadability and helping other ingredients glide over the skin or hair.
Peg/Ppg-18/12 Dimethicone’s Cosmetic Benefits/Uses
This ingredient is prized for the way it enhances the feel and performance of beauty products.
As an emollient, Peg/Ppg-18/12 Dimethicone forms a light, breathable film that fills in tiny surface gaps so skin and hair feel smoother. The silky layer helps trap moisture, reducing the look of dryness and roughness while giving formulas a luxurious slip that makes application effortless.
Who Can Use Peg/Ppg-18/12 Dimethicone
Peg/Ppg-18/12 Dimethicone is generally well tolerated by all skin types. Its lightweight feel suits oily and combination skin because it does not leave a greasy film, while its ability to smooth and lock in moisture helps dry or mature skin feel softer. Sensitive skin usually handles it well since the molecule is inert and non reactive, though anyone with a known silicone sensitivity should proceed with caution.
The ingredient is made synthetically from silica and petrochemical feedstocks, not from animals, so it is considered suitable for vegans and vegetarians. As always, individual brands may have different animal testing policies so check with the manufacturer if that is a concern.
Current safety data shows no known risks for pregnant or breastfeeding women when the ingredient is used topically in cosmetic amounts. Peg/Ppg-18/12 Dimethicone is too large to penetrate deeply and is not linked to hormonal activity. That said, this is not medical advice and expectant or nursing mothers should run any skincare choices past a doctor just to be safe.
The molecule does not make skin more sensitive to sunlight and does not interfere with sunscreens already in a routine. It also has no known interactions with common active ingredients like retinol or vitamin C, making it an easy addition to most regimens.
Potential Side Effects/Adverse Reactions
Reactions to topical Peg/Ppg-18/12 Dimethicone vary from person to person. The points below list potential side effects but they are uncommon when the ingredient is used correctly in a well formulated product.
- Mild skin irritation – occasional fleeting redness or itching, usually in very sensitive or compromised skin
- Contact dermatitis – rare allergic response that can show up as a rash or stinging
- Acne flare ups – a small number of highly clog prone users may notice breakouts if the product also contains heavier oils or waxes
- Eye irritation – temporary burning or blurriness if the product migrates into the eyes
If you experience any of these effects stop using the product and seek guidance from a healthcare professional.
Comedogenic Rating
Rating: 1 / 5
Peg/Ppg-18/12 Dimethicone earns a low score because its large, flexible molecules sit on the surface rather than seeping into pores, so they are unlikely to block follicular openings on their own. The ingredient forms a lightweight film that allows normal oil flow and water vapor to pass through, which further reduces clogging risk. While the polymer itself is non-pore-clogging, it can trap heavier oils or waxes layered beneath it, so an overall formula still matters. In most cases it is considered suitable for acne-prone or breakout-prone skin.
Summary
Peg/Ppg-18/12 Dimethicone is an emollient that smooths, softens and boosts spreadability by laying down a silky, breathable veil on skin or hair. Its mix of water-friendly PEG/PPG chains and a silicone backbone lets it blend into both watery and oily bases giving products a luxe touch without greasiness. Because it feels feather-light yet locks in moisture it shows up in everything from moisturizers and primers to hair serums and sunscreens.
The ingredient is popular with formulators who need a quick way to improve texture and slip though it may fly under the radar for everyday shoppers since it often sits mid-list on labels. Safety reviews find it inert non-sensitizing and unlikely to clog pores for most users. Still everyone’s skin is unique so it is wise to patch test any new product that features Peg/Ppg-18/12 Dimethicone before applying it widely.