What Is Peg/Ppg-20/29 Dimethicone?
Peg/Ppg-20/29 Dimethicone is a silicone based ingredient created by attaching polyethylene glycol (PEG) and polypropylene glycol (PPG) chains to dimethicone. This gives the molecule both water loving and oil loving parts, allowing it to mix substances that normally stay separate. It belongs to the broader family of siloxanes, materials first explored in the 1940s for their flexible feel and strong resistance to heat. Chemists later learned that adding PEG and PPG units made these silicones easier to blend into creams and lotions, which opened the door for everyday cosmetic use in the 1980s.
Manufacturing starts with dimethicone, a clear silicone fluid made from silica found in sand. Through controlled reactions, ethylene oxide adds the PEG sections while propylene oxide adds the PPG sections, giving an average ratio of 20 PEG units to 29 PPG units. The result is a smooth liquid that handles both water and oil ingredients with ease.
You will most often see Peg/Ppg-20/29 Dimethicone in lightweight moisturizers, serums, primers, sunscreens, leave-on hair products, color cosmetics like foundations, and sheet or wash-off masks where a silky feel and stable texture are key.
Peg/Ppg-20/29 Dimethicone’s Cosmetic Benefits/Uses
This ingredient is prized for one main role in beauty formulas.
Emulsifying: Peg/Ppg-20/29 Dimethicone helps water and oil based ingredients blend into a smooth, even product. This keeps creams from separating, improves spreadability, enhances the finished feel on skin or hair and can extend a product’s shelf life.
Who Can Use Peg/Ppg-20/29 Dimethicone
This silicone emulsifier is generally well tolerated by all skin types including dry, normal, combination sensitive and mature skin because it forms a breathable film that helps lock in moisture without a heavy greasy feel. People with extremely oily or acne prone skin who feel that any film former weighs them down might prefer to limit use or choose lighter formulations but the ingredient itself is not considered highly pore clogging.
Peg/Ppg-20/29 Dimethicone is made entirely through synthetic chemistry and contains no animal derived components so it is suitable for vegans and vegetarians.
No studies have flagged the ingredient as harmful during pregnancy or while breastfeeding. That said this is not medical advice and anyone who is pregnant or nursing should review all skincare products with their physician or midwife to be sure they meet individual needs.
The molecule does not increase photosensitivity so it will not make skin more prone to sunburn.
Potential Side Effects/Adverse Reactions
Individual responses to topical Peg/Ppg-20/29 Dimethicone can vary. The points below outline potential side effects that have been reported in rare cases. When the ingredient is properly formulated most users experience none of these issues.
- Temporary redness or stinging on very sensitive or compromised skin
- Rare allergic contact dermatitis resulting in itching swelling or rash
- Clogged pores or acne flare ups in individuals who react poorly to silicones
- Eye irritation if the product accidentally gets into the eyes
- Build up on hair shafts leading to dullness when used in leave on hair products without regular cleansing
If any adverse reaction occurs stop using the product and consult a healthcare professional.
Comedogenic Rating
Rating: 1/5. Peg/Ppg-20/29 Dimethicone forms a lightweight, breathable film that sits on the surface of skin rather than seeping deep into pores. Its large molecular size and partial water solubility make it unlikely to trap debris or excess oil, so it is considered low risk for clogging pores.
Because of this low score, the ingredient is generally suitable for people who are prone to acne or breakouts, provided the overall product is designed for their skin type.
As with any silicone the final formula matters; heavy creams packed with occlusive oils can still feel too rich for very oily skin even if the silicone itself is not pore clogging.
Summary
Peg/Ppg-20/29 Dimethicone is mainly an emulsifier that keeps water and oil phases blended, giving products a stable texture, smooth spread and silky feel. It achieves this by carrying both water loving PEG units and oil loving PPG units on a dimethicone backbone, allowing it to anchor itself between the two phases and hold them together.
Although not as famous as classic dimethicone or PEG-10 dimethicone, it is a quiet workhorse found in many lotions, sunscreens, foundations and hair serums where a light non greasy touch is preferred.
Current safety data shows very low irritation potential, no evidence of systemic toxicity and minimal comedogenicity. Still it is wise to patch test any new product since individual sensitivities vary.