Polyquaternium-7 is a highly substantive cationic copolymer that serves as a premier conditioning agent and film-former. It effectively neutralizes static and improves the tactile “slip” of both skin and hair formulations without leaving a heavy or greasy residue.
- INCI Name:
- Polyquaternium-7
- Chemical/Scientific Name:
- Copolymer of acrylamide and diallyldimethylammonium chloride
- Common Aliases:
- PQ7, DADMAC/Acrylamide Copolymer
| Category: | Texture Enhancers |
| Source Origin: | Synthetic |
| Comedogenic Rating: | 0 |
| Primary Industries: | Hair Care, Skin Cleansing, Personal Care |
| Solubility: | Soluble in Aqua and alcohol |
At a Glance: Properties & Effects
| Texture Enhancement | |
| Soothing/Calming | |
| Hydration/Moisture | |
| Irritation Risk |
- Primary Benefits:
- Provides excellent detangling and wet-combability in hair care.
- Improves foam stability and richness in surfactants.
- Creates a smooth, velvet-like feel on the skin after rinsing.
- Reduces static electricity by neutralizing surface charges.
- Potential Risks:
- Potential for “build-up” on hair if used in high concentrations without clarifying.
- Contains trace residual acrylamide, though levels are strictly regulated for safety.
Biological Action & Cosmetic Profile
Cationic nature defines the functional performance of this copolymer. Because hair and skin surfaces generally carry a negative (anionic) charge, the positively charged molecules of this ingredient are electrostatically attracted to the keratinous substrate. This attraction creates a thin, continuous film that smooths the cuticle of the hair or the stratum corneum of the skin. This film-forming ability is particularly valuable in rinse-off products where traditional oils might be washed away.Surface friction is significantly reduced through the application of this polymer. In hair care, this translates to improved manageability and a reduction in the mechanical damage caused by combing and styling. In skin care, especially within body washes and liquid soaps, it mitigates the drying effects of harsh surfactants like Lactic Acid or sulfates by providing a lubricating barrier.The molecular structure also contributes to foam rheology. When integrated into surfactant systems, it increases the viscosity of the lather, making the bubbles smaller, denser, and more stable. This aesthetic improvement enhances the consumer experience without interfering with the primary cleansing action of the formula.
Broader Applications & Origins
While primarily recognized for its role in hair conditioners and shampoos, this ingredient is frequently utilized in shaving creams and foaming facial cleansers. Its synthetic origin allows for high purity and batch-to-batch consistency. Manufacturers often supply it as a clear, viscous liquid diluted in Aqua, sometimes stabilized with preservatives like Sodium Benzoate.
Routine Integration
- Synergies:
- Anionic Surfactants: Enhances the lather and skin-feel of traditional cleansers.
- Glycerin: Works alongside humectants to lock in moisture via film formation.
- Proteins: Complements Hydrolyzed Wheat Protein or Hydrolyzed Keratin by sealing the hair shaft.
Clinical Consensus & Safety
The Cosmetic Ingredient Review (CIR) Expert Panel has evaluated this ingredient several times, concluding it is safe for use in cosmetic products. A primary safety concern involves residual acrylamide, a manufacturing byproduct; however, cosmetic grade versions must adhere to strict limits—typically less than 0.1 parts per million—ensuring no systemic risk to the consumer. Because it is a large polymer, it does not penetrate the skin barrier, further minimizing the risk of irritation or sensitization.
Is Polyquaternium-7 a silicone?
No, it is a synthetic cationic polymer, not a silicone. While it provides similar smoothing and detangling benefits to silicones like Dimethicone, it operates through different chemical mechanisms and is water-soluble, making it easier to rinse away in some formulations.
Does it cause hair build-up?
Because it is highly substantive, it can cling to the hair over time if used daily in leave-in products. However, unlike some heavy waxes or non-polar silicones, it can be removed with a standard clarifying shampoo containing Citric Acid or strong surfactants.
Is it safe for sensitive skin?
Yes, it is considered non-irritating. Its primary role is to improve the “hand-feel” of a product, and since it remains on the surface of the skin without penetrating, it rarely triggers adverse reactions in those with sensitive skin types.