Polyquaternium Conditioning Polymers Guide

Polyquaterniums in Cosmetic Formulas: Cationic Conditioning Polymers Explained

Formulators seeking smooth, tangle-free hair and silky skin feel consistently turn to one ingredient family: the polyquaterniums. These synthetic and semi-synthetic cationic polymers — designated by INCI names such as Polyquaternium-6, Polyquaternium-7, Polyquaternium-10, and Polyquaternium-11 — carry a permanent positive charge that makes them highly substantive to the negatively charged surfaces of hair and skin. The result is measurable wet- and dry-combing improvement, reduced static and flyaway, and a soft conditioning film that transforms sensory perception. Yet selecting the wrong polyquaternium, or mishandling it in an anionic surfactant base, can cause haze, precipitation, limp hair, or stubborn buildup. This guide breaks down the chemistry, the families, the comparative performance, formulation best practices, and the global regulatory status of polyquaternium conditioning polymers.

At a Glance

Function	Target Applications	Key Specifications	Compliance Status
Cationic conditioning, anti-static, film-forming, viscosity contribution, deposition aid for silicones and actives	Rinse-off and leave-on hair care (shampoos, conditioners, masks, styling), body wash, facial cleansers, moisturizers, shave gels	Supplied as aqueous solutions (8–40% solids) or powders; cationic charge density from ~0.5 to ~6 meq/g; molecular weights from ~10⁵ to >10⁶ Da	CIR-reviewed as safe as used in present practices; listed in the EU CosIng database with no Annex II/III restrictions for common grades; listed in China IECIC
Wet-comb force reduction, surface lubricity, sebum control films, clear-gel conditioning	Clear shampoos, 2-in-1 cleansers, color-protection lines, sulfate-free systems, bar cleansers, wipes	Typical use levels 0.05–2.0% active; stable pH 4–9 for most grades; compatible with anionic/amphoteric surfactant systems depending on charge density	US: MoCRA (2022) ingredient listing framework; EU: Regulation (EC) No 1223/2009 compliant; Japan: positive list systems; safety supported by SCCS review principles

Mechanism of Action: How Cationic Polymers Condition

Production and Synthesis Routes

The polyquaterniums are not a single chemistry but a numbered INCI series of quaternary ammonium polymers. The most important industrial routes include:

Polyquaternium-6 (CAS 26062-79-3) is produced by free-radical cyclopolymerization of diallyldimethylammonium chloride (DADMAC), yielding a homopolymer in which the quaternary ammonium group sits inside a pyrrolidinium ring within the backbone:

n [CH ₂=CH–CH ₂–N ⁺(CH ₃) ₂–CH ₂–CH=CH ₂] Cl ⁻ → [–CH ₂–CH–CH ₂–N ⁺(CH ₃) ₂–CH ₂–CH–] _n nCl ⁻

Polyquaternium-7 (CAS 26590-05-6) is a copolymer of DADMAC with nonionic acrylamide. The acrylamide dilutes the cationic charge along the chain, which is why PQ-7 tolerates anionic surfactant systems far better than PQ-6. Commercial PQ-7 is typically sold as an 8–10% aqueous solution. For sourcing, the Polyquaternium-7 supply listing covers major producers and grades.

Polyquaternium-10 (CAS 68610-92-4) is a cationic cellulose ether: hydroxyethyl cellulose is etherified with the quaternizing reagent 3-chloro-2-hydroxypropyltrimethylammonium chloride (the same reagent used to cationize guar), grafting trimethylammonium side groups onto the polysaccharide:

HEC–OH + Cl–CH ₂–CH(OH)–CH ₂–N ⁺(CH ₃) ₃ Cl ⁻ → HEC–O–CH ₂–CH(OH)–CH ₂–N ⁺(CH ₃) ₃ Cl ⁻ + HCl

Polyquaternium-11 (CAS 53633-54-8) is the quaternized copolymer of vinylpyrrolidone and dimethylaminoethyl methacrylate, giving a film-forming polymer favored in mousses, gels, and styling sprays.

Deposition and Conditioning Mechanism on Hair and Skin

The conditioning effect is fundamentally electrostatic. Human hair has an isoelectric point near pH 3.7, so at typical cosmetic pH (4.5–6.5) the cuticle surface carries a net negative charge. Quaternary ammonium groups are permanently ionized — independent of pH — so polyquaternium chains adsorb strongly and often irreversibly onto the fiber surface. This adsorbed polymer layer:

• Lubricates the cuticle, lowering the friction coefficient and cutting wet-combing forces dramatically — the key instrumental proof of conditioning performance.
• Neutralizes static charge, suppressing flyaway after towel-drying and brushing.
• Forms a flexible film that smooths lifted cuticle scales, improving shine and alignment.
• Acts as a deposition aid: in 2-in-1 shampoos, dilution-induced coacervation between the cationic polymer and anionic surfactant (e.g., sodium laureth sulfate) forms a viscous phase that deposits onto hair during rinsing, carrying silicones and oils with it.

Charge density and molecular weight govern substantivity: high-charge, high-molecular-weight polymers deposit more strongly but risk buildup and over-conditioning, while low-charge copolymers give a lighter, cleaner feel. On skin, the same adsorption produces a perceptible silky, "slip" film used in body washes, shave products, and moisturizers — a cornerstone of hair conditioning agents and skin-feel modification generally. Biodegradability varies: cellulosic and guar-based cationics break down more readily than highly substituted vinyl homopolymers such as PQ-6.

Chemical Families: Classifying the Polyquaternium Series

With more than 100 numbered INCI entries, the polyquaternium family is best understood as three structural classes, each with distinct handling and performance trade-offs.

Synthetic Vinyl-Type Cationics (PQ-6, PQ-7, PQ-16, PQ-46)

These petrochemical-derived polymers are built by free-radical polymerization of quaternized vinyl or allyl monomers. Polyquaternium-6, the DADMAC homopolymer, has the highest charge density of the common grades and delivers powerful conditioning and even some preservative potentiation — but it forms insoluble complexes with anionic surfactants and is therefore largely restricted to conditioners and treatments. PQ-7, the DADMAC/acrylamide copolymer, is the workhorse of the class: low charge, excellent anionic compatibility, and a light skin feel at low cost. Its limitations are modest conditioning at low doses and a slightly tacky feel at high doses. These vinyl polymers are inexpensive and robust, but their biodegradability is limited.

Cationic Cellulose Ethers (PQ-4, PQ-10, PQ-46-type)

Polyquaternium-10 and the related Polyquaternium-4 attach quaternary groups to a hydroxyethyl cellulose backbone, combining polysaccharide substantivity with a clean, non-tacky after-feel. PQ-10 is the most widely used cationic in clear shampoos because it is compatible with anionic surfactants at typical use levels and even contributes mild thickening. Trade-offs: higher cost than PQ-7, sensitivity to high salt levels, and lower humidity resistance than cationic silicone systems. PQ-4 offers higher charge for deeper conditioning in treatments.

Natural-Derived Polysaccharide Cationics (Guar Hydroxypropyltrimonium Chloride)

Guar gum, a galactomannan from the guar bean, is cationized with the same trimethylammonium epoxide reagent used for PQ-10. Guar hydroxypropyltrimonium chloride delivers efficient wet-conditioning in clear shampoos, cold-processes easily, and carries a strong sustainability narrative — a natural-based backbone with better biodegradability than vinyl polymers. Limitations include supply variability, haze risk at high use levels in some surfactant systems, and a heavier deposition feel than PQ-10. It is often paired with PQ-7 or PQ-10 in hybrid conditioning systems.

Comparative Matrix: Polyquaterniums vs. Alternative Conditioning Polymers

INCI Name / CAS	Charge Density	Anionic Surfactant Compatibility	Feel / Sensory	Best Applications
Polyquaternium-6 (26062-79-3)	Very high (~6 meq/g)	Poor — complexes/precipitates with sulfates	Heavy, substantive conditioning	Rinse-off conditioners, hair masks, treatments
Polyquaternium-7 (26590-05-6)	Low (~1–2 meq/g)	Excellent — standard in sulfate shampoos	Light, clean, low-tack	Clear shampoos, body wash, 2-in-1 cleansers
Polyquaternium-10 (68610-92-4)	Moderate	Good — stays clear in most anionic systems	Silky, cushioned, non-tacky	Premium shampoos, shower gels, leave-on skin care
Polyquaternium-11 (53633-54-8)	Moderate	Good in PVP-containing and alcohol systems	Firm flexible film, slight stiffness	Mousses, gels, styling sprays, conditioners
Polyquaternium-16 (95144-24-4)	Moderate	Good	Light film, glossy finish	Leave-in conditioners, styling lotions, mascara
Guar Hydroxypropyltrimonium Chloride (65497-29-2)	Tunable (low to high)	Good in most anionic shampoos	Soft, natural, slightly heavier	Natural-positioned shampoos, sulfate-free lines

Formulation SOP and Best Practices

Successful use of polyquaterniums is a matter of matching charge density to the surfactant system and controlling polymer order of addition. The table below summarizes typical use levels drawn from supplier technical literature and standard formulation practice:

Polymer	Typical Use Level (active)	Recommended pH	Addition / Processing Notes
Polyquaternium-7	0.1–1.0%	4.0–8.0	Add liquid grade to the water phase before surfactants or directly into the finished base with good agitation
Polyquaternium-10	0.1–0.5% (up to 1.0% in treatments)	4.5–7.0	Pre-disperse powder in warm water (40–50 °C) and let hydrate fully before adding surfactants; avoid dumping powder into concentrated surfactant gel
Polyquaternium-6	0.1–0.5%	3.5–7.0	Use only in essentially anionic-free systems; add to the water phase of conditioners and masks
Polyquaternium-11	0.5–2.0%	5.0–8.0	Solution or powder form; add after neutralization of carbomer gels to avoid viscosity loss
Guar Hydroxypropyltrimonium Chloride	0.1–0.5%	4.5–8.0	Pre-swell in water or glycerin slurry before surfactant addition; hydrates slowly — allow 20–30 minutes

WARNING — Common Processing Mistakes:

Adding high-charge polymers (PQ-6, high-substitution guar) directly to concentrated anionic surfactant bases causes immediate complex coacervation and irreversible haze or precipitate.
Salt thickening after polymer addition can shock the system and throw out polymer–surfactant complexes; verify clarity after NaCl addition, not before.
Over-dosing conditioning polymer produces limp, flat hair, visible flake-like buildup, and faster sebum-induced re-soiling — a leading cause of consumer complaints in fine-hair segments.
Adding PQ-11 before neutralizing a carbomer gel collapses viscosity and can string the gel.

BEST PRACTICE — Formulator Tips:

Use dilution-induced coacervation deliberately: pairing PQ-7 or PQ-10 with sodium laureth sulfate creates a deposition mechanism that boosts silicone delivery in 2-in-1 shampoos.
Screen candidates with a dia-ctrometer wet-comb measurement on brown, virgin hair tresses — reduction in combing work of 30–60% is a realistic target at 0.2–0.3% active.
For "clean" and sulfate-free positioning, combine guar hydroxypropyltrimonium chloride with PQ-10 for a natural-derived story with proven clear-gel performance.
Premix powders into glycerin or propylene glycol before aqueous dispersion to prevent fisheyes and speed hydration.
Check preservative efficacy — cationic polymers can bind anionic preservative systems; validated preservative challenge testing (ISO 11930) is mandatory.

Global Regulatory and Compliance Guide

Polyquaterniums enjoy a long, well-documented safety history. The table below summarizes the principal jurisdictions and frameworks a global formulator must address:

Jurisdiction / Body	Framework	Status of Polyquaterniums
United States	CIR review; MoCRA (2022) ingredient listing	CIR has reviewed numerous polyquaterniums (including PQ-7, PQ-10, PQ-11 and related cationics) and found them safe as used in present cosmetic practices; no FDA color-additive-type restrictions apply
European Union	Regulation (EC) No 1223/2009; CosIng database	Common polyquaterniums are listed in CosIng with no entries in Annex II (prohibited) or Annex III (restricted); safety assessment per Article 10 and the SCCS Notes of Guidance is the responsibility of the Responsible Person
China	IECIC (Inventory of Existing Cosmetic Ingredients); CSAR	Widely used polyquaterniums and cationic guar appear in the IECIC and may be used in registered/notified cosmetics in line with NMPA technical requirements
Japan / Korea	MHLW positive list; MFDS cosmetic rules	Permitted as quasi-drug/cosmetic conditioning ingredients within established use practices; no specific concentration limits for standard polyquaterniums
Quality standards	ISO 11930 (preservation), ISO 22716 (GMP), pharmacopeial monographs	Supplier specifications typically control residual monomers (e.g., DADMAC, acrylamide), heavy metals, and microbial limits; formulators should request current certificates of analysis and residual-monomer data

Frequently Asked Questions

What is the difference between Polyquaternium-7 and Polyquaternium-10?

PQ-7 is a synthetic copolymer of DADMAC and acrylamide with a low cationic charge, sold as an economical liquid that excels in clear anionic shampoos and body washes. PQ-10 is a cationic hydroxyethyl cellulose with moderate charge, usually a powder, giving a silkier, more cushioned feel, better skin substantivity, and a stronger premium positioning — at a higher price point. Many shampoos use both together to balance cost and sensory.

Are polyquaterniums safe, and do they build up on hair?

CIR panels have evaluated many polyquaterniums and concluded they are safe as used in cosmetics. Buildup is a cosmetic rather than safety issue: high-charge polymers applied repeatedly without clarifying can accumulate, weighing fine hair down. Alternating with a clarifying shampoo or limiting cationic polymer concentration to about 0.3% active in daily-wash products keeps deposition in the intended range.

Why did my clear shampoo turn hazy after adding the conditioning polymer?

Haze signals polymer–surfactant complex formation. Either the charge density of the chosen polymer is too high for the anionic level (switch from PQ-6 to PQ-7 or PQ-10), the total actives are too concentrated at the point of addition (dilute or change order of addition), or salt added for thickening pushed the system past its compatibility limit. A compatibility ladder study across polymer dose and salt level will map the clear window.

Are there natural or biodegradable alternatives to synthetic polyquaterniums?

Cationic guar (guar hydroxypropyltrimonium chloride) and cationic celluloses like PQ-10 are natural-derived options with better biodegradability than vinyl-type polymers such as PQ-6 or PQ-16. For fully sulfate-free and naturally positioned systems, guar-based cationics combined with natural emollients deliver credible conditioning performance while supporting clean-beauty claims.

References

Romanowski P. Polyquaterniums in Cosmetic Formulas. UL Prospector Knowledge Center, July 26, 2023.
Cosmetic Ingredient Review. Final Report on the Safety Assessment of Polyquaternium-7. International Journal of Toxicology.
Cosmetic Ingredient Review. Final Report on the Safety Assessment of Polyquaternium-10. International Journal of Toxicology.
Cosmetic Ingredient Review. Safety Assessment of Polyquaternium Polymers as Used in Cosmetics. CIR, Washington, DC.
Regulation (EC) No 1223/2009 of the European Parliament and of the Council on Cosmetic Products. Official Journal of the European Union.
Scientific Committee on Consumer Safety (SCCS). The SCCS Notes of Guidance for the Testing of Cosmetic Ingredients and Their Safety Evaluation.
European Commission. CosIng — Cosmetic Ingredients Database: Polyquaternium-6, Polyquaternium-7, Polyquaternium-10, Polyquaternium-11 entries.
Personal Care Products Council. International Cosmetic Ingredient Dictionary and Handbook: INCI Names for Polyquaternium Series.
Modernization of Cosmetics Regulation Act of 2022 (MoCRA). United States Congress, Public Law 117-328.
ISO 11930:2019. Cosmetics — Microbiology — Evaluation of the antimicrobial protection of a cosmetic product.
ISO 22716:2007. Cosmetics — Good Manufacturing Practices (GMP) — Guidelines on Good Manufacturing Practices.
Japanese Ministry of Health, Labour and Welfare. Standards for Cosmetics (positive list of quasi-drug ingredients).
Journal of the Society of Cosmetic Chemists. Studies on the deposition and substantivity of cationic polymers on keratin fibers.
Journal of the Society of Cosmetic Chemists. Instrumental wet-combing methods for evaluating hair conditioning efficacy.
China NMPA. Safety and Technical Standards for Cosmetics and Inventory of Existing Cosmetic Ingredients in China (IECIC).