What Is Phenylpropyldimethylsiloxysilicate?
Phenylpropyldimethylsiloxysilicate is a silicone-based ingredient created by linking small units of silicic acid with a phenylpropyl group. The result is a clear, lightweight fluid that feels silky on skin and hair. First explored by chemists looking for flexible water-resistant coatings in the late 20th century, it soon found a place in beauty care because of its smooth feel and long-lasting finish.
The material is produced through a controlled reaction in which dimethylsiloxane chains are bonded to phenylpropyl silane under heat and a catalyst. Once the reaction is complete the mixture is purified to remove by-products, yielding a high-purity cosmetic grade fluid.
You will spot this silicone in a wide range of formulas such as long-wear foundations, primers, waterproof mascaras, lipsticks, sunscreens, hair serums, leave-in conditioners, anti-frizz sprays, facial moisturizers and setting sprays. Its ability to form a flexible film that resists water and oils makes it especially popular in products that promise extended wear or humidity protection.
Phenylpropyldimethylsiloxysilicate’s Cosmetic Benefits/Uses
This versatile silicone supports both skin and hair care goals through several key actions:
- Film forming: Creates a breathable yet water-resistant layer that helps makeup last longer, prevents color transfer and boosts sun protection when used with UV filters.
- Hair conditioning: Coats strands in a thin protective sheath that smooths cuticles, adds shine and makes combing easier while shielding hair from humidity.
- Emollient: Glides over skin to soften rough spots and give products a silky slip that improves spreadability without a greasy feel.
- Skin conditioning: Helps lock in moisture, leaves skin feeling smooth and enhances the overall sensory experience of creams and lotions.
Who Can Use Phenylpropyldimethylsiloxysilicate
This silicone suits most skin types thanks to its lightweight breathable film. Dry and normal skin tend to appreciate the softening feel while oily or combination skin benefit from the non-greasy texture. Extremely acne-prone users who react to any film formers may want to monitor how their skin responds but the ingredient itself has a very low tendency to clog pores.
Phenylpropyldimethylsiloxysilicate is produced synthetically without animal derivatives so it is suitable for vegans and vegetarians. It is also compatible with halal and kosher formulations when manufactured under the correct guidelines.
The molecule is large and stays on the surface of skin which limits absorption, so it is generally considered safe for pregnant or breastfeeding women. This is not medical advice and anyone who is pregnant or nursing should clear all personal care products with a doctor to be safe.
The ingredient does not cause photosensitivity and can even help stabilize UV filters in sunscreens. It is odorless, colorless and typically gentle around the eyes, making it a flexible choice in many types of cosmetics.
Potential Side Effects/Adverse Reactions
Individual reactions to topical Phenylpropyldimethylsiloxysilicate can vary. The points below outline potential side effects, though most people will not experience them when the ingredient is used correctly in a finished product.
- Mild pore clogging or breakouts in very acne-prone skin when used in heavy or occlusive formulas
- Rare cases of contact dermatitis including redness itching or irritation
- Product build-up on hair shafts leading to temporary dullness or weighed-down feel if cleansing is inadequate
- Stinging or watering if the raw ingredient or a high-level formula accidentally gets into the eyes
If you experience any of these effects stop using the product and seek guidance from a healthcare professional or dermatologist.
Comedogenic Rating
Rating: 1/5
Phenylpropyldimethylsiloxysilicate sits on the surface of skin and has a large molecular size that prevents it from sinking into pores. It creates a breathable film rather than a heavy occlusive layer, so the chance of blocked pores is low. The rating is not a perfect zero because any film former can trap existing oil or debris if used in very rich formulas or if skin is not cleansed thoroughly.
Most people prone to acne can use products containing this ingredient without issues, though very reactive skin types should stay alert to how their skin responds.
Keep in mind that overall formula design, the presence of other pore clogging ingredients and inadequate cleansing play a bigger role in breakouts than this silicone itself.
Summary
Phenylpropyldimethylsiloxysilicate works as a film former, hair conditioner, emollient and skin conditioner. It lays down a thin flexible coat that resists water and oils, smooths cuticles on hair, improves spreadability in creams and locks in light moisture without feeling greasy. Those qualities make it a go to choice in long wear foundations, primers, waterproof mascaras, sunscreens and anti-frizz sprays, even though its name is hardly famous outside ingredient lists.
Safety reviews place this silicone in the low risk category thanks to minimal absorption and a long history of use with few reports of irritation. Still, every skin is unique so patch test any new product that features it to be sure it fits your personal needs.