What Is Epsilon Caprolactone Peg/Ppg-23/34 Copolymer?
Epsilon Caprolactone PEG/PPG-23/34 Copolymer is a lab made ingredient created by linking together three building blocks: ethylene oxide, propylene oxide and epsilon caprolactone. Chemists combine an average of 23 units of ethylene oxide with 34 units of propylene oxide, then attach caprolactone rings along the chain. The result is a lightweight waxy substance that dissolves easily in water and oils, letting it blend well with many other cosmetic ingredients.
The technology behind this copolymer grew out of research in the late 1980s when formulators looked for gentler alternatives to heavy mineral oils and animal derived lanolin. By tweaking the ratios of ethylene oxide and propylene oxide, scientists discovered they could fine-tune how the material feels on skin and hair. Caprolactone units add flexibility and boost the ability to hold onto moisture, which quickly made the copolymer popular in personal care labs.
The production process starts with controlled ring-opening polymerization of epsilon caprolactone. Next, ethylene oxide and propylene oxide are added in sequence under carefully monitored temperature and pressure. The final copolymer is purified, then milled into a soft powder or viscous liquid ready for use in formulations.
You will most often find Epsilon Caprolactone PEG/PPG-23/34 Copolymer in rinse-off and leave-in hair conditioners, styling creams, curl definers, moisturizing shampoos, facial moisturizers, lightweight body lotions and soothing after-sun gels. Its balance of water loving and oil loving parts helps products spread smoothly and leave behind a soft, conditioned feel.
Epsilon Caprolactone Peg/Ppg-23/34 Copolymer’s Cosmetic Benefits/Uses
This multifunctional ingredient supports both skin and hair care formulas in two key ways:
- Hair Conditioning: Forms a thin flexible film around each strand which smooths the cuticle, reduces frizz, adds slip for easier detangling and imparts a silky touch without weighing hair down
- Emollient: Softens the skin surface by filling in microscopic gaps between cells, helping to trap moisture and leaving skin feeling smooth comfortable and non-greasy
Who Can Use Epsilon Caprolactone Peg/Ppg-23/34 Copolymer
This ingredient is gentle enough for all skin types including dry, oily, combination and sensitive because it is non-occlusive and has a light feel that rarely clogs pores or traps heat. People with very reactive skin may still wish to monitor how their skin feels when introducing any new product but in standard formulas the copolymer is considered low risk.
Epsilon Caprolactone Peg/Ppg-23/34 Copolymer is fully synthetic and contains no animal-derived material so it is suitable for both vegans and vegetarians.
No research suggests that the ingredient poses a special risk during pregnancy or while breastfeeding. The large polymer molecules stay on the surface of skin and hair rather than entering the bloodstream. Still, this is not medical advice and anyone who is pregnant or nursing should show the full ingredient list of any cosmetic product to a healthcare professional to be sure it fits their personal needs.
The copolymer does not make skin more sensitive to sunlight and there are no known issues with daytime use.
Potential Side Effects/Adverse Reactions
Side effects from topical use of Epsilon Caprolactone Peg/Ppg-23/34 Copolymer vary from person to person. The points below describe potential reactions though they are uncommon when the ingredient is used in a properly formulated product.
- Mild skin redness or itching in individuals who are highly sensitive to synthetic polymers
- Transient stinging if applied to freshly shaved or broken skin
- Build-up on very fine hair if used in high-hold styling products which may lead to a weighed-down feel
- Rare allergic contact dermatitis in people with a specific sensitivity to polyethylene glycol or propylene glycol derivatives
If you notice any persistent discomfort stop using the product and consult a healthcare professional.
Comedogenic Rating
Rating: 1 out of 5
Epsilon Caprolactone PEG/PPG-23/34 Copolymer earns a low score because its large water-soluble molecules sit on the surface rather than seeping into pores and it leaves only a light breathable film. It contains no heavy oils or waxes that typically trigger blockage so it is generally suitable for people prone to acne or breakouts.
Comedogenicity can still rise if the ingredient is blended with richer butters or occlusive silicones in a finished product so always look at the full formula, not just one component.
Summary
Epsilon Caprolactone PEG/PPG-23/34 Copolymer works as a hair conditioner and skin-softening emollient. It forms a thin flexible coating that smooths hair cuticles for less frizz and fills the tiny gaps between skin cells to boost softness and trap light moisture without greasiness.
While it is not a headline ingredient found in every beauty commercial it is a quiet favorite among formulators who need a reliable lightweight polymer that plays well with both water and oils. You will spot it most often in modern hair conditioners leave-in creams and sheer body lotions.
Safety studies and decades of consumer use show a very low risk of irritation or pore clogging. Still, everyone’s skin is unique so perform a simple patch test when trying any new product that contains this copolymer to make sure it suits your personal needs.