What Is Polyquaternium-79?
Polyquaternium-79 is a synthetic polymer created by first crosslinking the plant-derived surfactant decyl glucoside with 1,3-dichloro-2-propanol. Any remaining chloropropanol groups are then quaternized with stearyldimethylamine, giving the finished molecule its permanent positive charge. This cationic nature helps it cling to hair and skin surfaces, boosting performance in cleansing and conditioning formulas.
The polyquaternium family emerged in the 1970s as chemists looked for gentler, more effective replacements for harsh soaps. Polyquaternium-79 is one of the newer members, developed to pair the mildness of sugar-based surfactants with the conditioning strength of long-chain quats. Its adoption grew quickly in hair care when formulators noticed it left strands smoother without weighing them down.
Manufacturing starts with fermenting plant sugars to obtain decyl glucoside. This mild cleaner is reacted with 1,3-dichloro-2-propanol under controlled heat and pH to form a three-dimensional polymer. Finally, stearyldimethylamine is added to quaternize the remaining reactive sites, locking in the positive charges that define the ingredient’s performance.
You will usually spot Polyquaternium-79 in shampoos, conditioners, co-wash products, cleansing balms, leave-in detanglers, anti-frizz serums and some cream-based facial cleansers where a silky rinse feel is desired.
Polyquaternium-79’s Cosmetic Benefits/Uses
This versatile polymer pulls triple duty in formulations, helping products clean effectively while leaving hair or skin soft and stable.
- Cleansing: Its mild surfactant backbone lifts away dirt and excess oil while reducing the harsh squeaky feel often left by stronger detergents
- Hair Conditioning: The positive charges bind to the negatively charged cuticle, smoothing rough spots, reducing static, improving manageability and adding a light protective film that enhances shine
- Emulsifying: It helps blend oil and water phases, stabilizing creamy or milky textures so products stay uniform during storage and use
Who Can Use Polyquaternium-79
Because it is both mild and lightweight, Polyquaternium-79 suits most skin and hair types, including dry, normal, oily and even sensitive conditions. Its positive charge lets it condition without leaving a greasy film so it rarely weighs down fine strands or clogs pores.
The polymer is produced from plant sugars and synthetic reagents, with no animal-derived inputs, making it generally acceptable for vegans and vegetarians. As always, ethical shoppers should verify the finished product’s overall cruelty-free status with the brand.
Current safety data show no systemic absorption, so topical use is considered low risk for people who are pregnant or breastfeeding. This is not medical advice; anyone expecting or nursing should run any cosmetic routine past a qualified physician to be safe.
Polyquaternium-79 does not make skin more sensitive to sunlight and can be worn alongside daily sunscreen without special precautions. It is also color-safe for chemically treated hair and compatible with most styling routines.
Potential Side Effects/Adverse Reactions
Responses to any cosmetic ingredient differ among individuals. The effects listed below are possible but uncommon when Polyquaternium-79 is used in a properly formulated product.
- Mild scalp or skin irritation such as redness itching or dryness
- Eye stinging or watering if product rinses into the eyes
- Build-up on hair that may leave strands dull or limp when the ingredient is used excessively without clarifying washes
- Rare allergic contact dermatitis in people sensitive to cationic polymers
If you experience any of these issues discontinue use and seek advice from a healthcare professional or dermatologist.
Comedogenic Rating
Rating: 0 / 5 (non-comedogenic)
Polyquaternium-79 is a large water-soluble polymer that carries a positive charge, so it stays mostly on the surface and rinses away with water instead of seeping into pores or mixing with skin oil. Because it is not oily or waxy it has virtually no tendency to block follicles, which earns it the lowest possible score.
That means it is generally suitable for people who break out easily.
One note: if the rest of a formula is rich in heavy butters or silicones, those ingredients may affect pore-clogging potential even though Polyquaternium-79 itself does not.
Summary
Polyquaternium-79 cleans, conditions hair and stabilizes emulsions thanks to its mild sugar-based surfactant backbone and permanently positive charge that helps it cling where needed. The result is gentle cleansing, smoother strands, less static and creams that stay evenly blended.
The ingredient is not as famous as classics like polyquaternium-10 yet it is gaining ground in newer sulfate-free shampoos, co-washes and silky facial cleansers because it delivers a soft feel without heaviness.
Current research shows it is low risk for irritation or systemic absorption, making it a safe pick for most users. As with any new product it is smart to do a quick patch test first just to be safe.