What Is Polyquaternium-35?
Polyquaternium-35 is a man-made, water-soluble polymer built from small acrylic units that carry permanent positive charges. These charges come from quaternary ammonium groups, which are why the ingredient sits in the “polyquaternium” family. Unlike plant oils or mineral waxes, it has no natural source; it is created entirely through controlled lab reactions.
The polymer is produced by reacting dimethylaminoethyl methacrylate with methyl sulfate, then linking the resulting quaternized units together in long chains during a process called free-radical polymerization. The finished material looks like a clear to slightly hazy liquid or a fine powder that dissolves easily in water.
Polyquaternium-35 first appeared in hair sprays in the 1970s when formulators needed a flexible, humidity-resistant fixative that would not leave hair stiff or flaky. Its ability to form an invisible, weightless film made it a quick favorite. Today it is found in an array of products such as styling gels, mousses, leave-in conditioners, shampoos, skin creams, sheet masks, sunscreens, make-up primers and even temporary tattoo films.
Polyquaternium-35’s Cosmetic Benefits/Uses
When added to a formula Polyquaternium-35 performs two main jobs that improve how a product feels and works.
- Antistatic: The positive charges in the polymer neutralize the negative charges that build up on hair or skin. This cuts down on static flyaways in hair, helps strands lie smoothly and keeps clothing from clinging to the skin.
- Film forming: It creates a thin, breathable coating that locks in moisture, boosts shine and enhances the staying power of pigments or styling agents. In skin care this film gives a soft, silky finish and can make lotions feel smoother while in hair care it offers light hold and humidity resistance.
Who Can Use Polyquaternium-35
Polyquaternium-35 is generally well tolerated by all skin and hair types. Its lightweight, water-soluble film suits oily or acne-prone skin because it does not trap excess sebum, yet it also helps dry or mature skin hold on to moisture. Very sensitive skin may react to any cationic polymer, so those users should proceed with a bit more caution.
The ingredient is made entirely in the lab with no animal-derived components, making it suitable for both vegans and vegetarians.
Current safety assessments show no reproductive or developmental concerns, so products containing Polyquaternium-35 are considered acceptable for pregnant or breastfeeding women. This is not medical advice; anyone who is expecting or nursing should review all personal care products with a qualified healthcare professional.
Polyquaternium-35 does not absorb UV light or alter the skin’s response to sunlight, so it is not linked to photosensitivity. It is also color-safe for dyed hair and rinses out easily, helping to prevent heavy buildup.
Potential Side Effects/Adverse Reactions
Responses to topical Polyquaternium-35 vary from person to person. The points below list potential side effects, but most users will not experience them when the ingredient is included at appropriate levels in well-formulated products.
- Mild skin or scalp irritation such as redness or itching
- Allergic contact dermatitis in individuals sensitive to quaternary ammonium compounds
- Product flaking or residue if used in very high concentrations
- Temporary limp or weighed-down hair when multiple styling products containing the polymer are layered without proper cleansing
If any unwanted reaction occurs stop using the product and consult a healthcare professional for guidance.
Comedogenic Rating
Rating: 0–1 (virtually non-comedogenic)
Polyquaternium-35 is highly water-soluble and forms a breathable film that rinses off easily, so it does not sit in pores the way heavier oils or waxes can. It lacks fatty acids that feed acne-causing bacteria and its positive charge helps it bind to hair and skin surfaces instead of migrating into follicles. Because of this, it rarely triggers or worsens breakouts.
Suitable for acne-prone or congestion-prone skin, especially in rinse-off or lightweight leave-on formulas.
Only products that combine Polyquaternium-35 with very occlusive ingredients could raise a clogging risk, not the polymer itself.
Summary
Polyquaternium-35 works mainly as an antistatic agent and a film former. Its permanent positive charges neutralize static on hair and skin while its thin water-soluble film locks in light moisture adds slip boosts shine and keeps styling or make-up in place without stiffness.
It enjoys steady popularity in hair sprays gels and modern skin care because it offers flexible hold a silky feel and easy washout at modest cost though it does not have the name recognition of trendier naturals.
Current research and long consumer use point to a high safety profile with low irritation potential and virtually no comedogenicity. As with any new cosmetic ingredient it is wise to patch test a product before full use to make sure your individual skin or scalp agrees with it.