polyquaternium11

Polyquaternium-11 is a synthetic, water-soluble cationic polymer widely used as a conditioning and thickening agent in cosmetic formulations. It belongs to the polyquaternium family and is produced by polymerizing diallyldimethylammonium chloride into long chains bearing quaternary ammonium groups. The polymer carries a positive charge along its backbone, which promotes binding to negatively charged surfaces such as hair and skin.

Its high molecular weight and cationic nature enable it to form a flexible film on hair fibers, reducing friction, static, and tangling. In typical use, it provides slip and conditioning without a heavy residue, and can improve wet combability and smoothness. The effect varies with molecular weight and concentration.

Common applications include shampoos, conditioners, and styling products, where it acts as a conditioning polymer and, in some formulas, as a viscosity modifier. It is generally compatible with a range of surfactants and other cosmetic ingredients, but high levels of anionic components can diminish its conditioning performance due to charge interactions.

Safety assessments in cosmetic use have found polyquaternium-11 to be safe at standard use levels (for example around 0.1–1%). It is considered non-irritating for many users, though formulations should follow good manufacturing practice and label guidance. Regulatory acceptance varies by region and formulation type.

Environmental fate of polyquaternium-11 depends on conditions and treatment; like many synthetic polymers used in personal care products, it may be persistent in some environments and is not typically readily biodegradable. Manufacturers provide handling and disposal guidance relevant to their products.