PEG-32 is a versatile, water-soluble polymer used as a humectant, solvent, and consistency regulator in skincare and pharmaceutical formulations. Its primary role involves improving product spreadability and preventing moisture loss while acting as a stable vehicle for other active ingredients.
- INCI Name:
- PEG-32
- Chemical/Scientific Name:
- Polyethylene Glycol 1500; Poly(oxy-1,2-ethanediyl)
- Common Aliases:
- Macrogol 1500, Polyoxyethylene (32)
| Category: | Moisturizers |
| Source Origin: | Synthetic |
| Comedogenic Rating: | 0 |
| Primary Industries: | Cosmetic, Pharmaceutical, Food |
| Solubility: | Water-soluble |
At a Glance: Properties & Effects
| Hydration/Moisture: | |
| Texture Enhancement: | |
| Formula Stability: | |
| Irritation Risk: |
Primary Benefits:
- Attracts water to the skin surface to improve hydration.
- Functions as an effective binder for solid or semi-solid formulations like bar soaps and sticks.
- Enhances the solubility of active substances in Aqua.
- Improves the slip and “skin feel” of creams without adding greasiness.
Potential Risks:
- May act as a penetration enhancer, potentially increasing the absorption of other ingredients.
- Minimal risk of hypersensitivity in individuals with known PEG allergies.
Biological Action & Cosmetic Profile
As a medium-molecular-weight polymer, this substance consists of approximately 32 units of ethylene oxide. The chemical structure is inherently hydrophilic, allowing it to bind to water molecules via hydrogen bonding. When applied topically, it creates a breathable film that slows down transepidermal water loss (TEWL) and keeps the stratum corneum supple. Unlike traditional oils, it provides this moisturizing effect without a heavy or occlusive residue.
Formulators often employ this waxy solid to adjust the viscosity and stability of complex emulsions. It functions as a bridge between various components, ensuring that pigments and active powders remain evenly dispersed throughout the product’s shelf life. Because it is non-volatile, it also prevents cosmetic products like toothpastes and creams from drying out or “crusting” at the opening of the container.
The solvency profile of this polymer is particularly valuable for stabilizing poorly soluble ingredients. It can help integrate substances that would otherwise require high concentrations of harsh alcohols. By modifying the surface tension of the liquid phase, it promotes a more uniform application of the final product on the skin or hair.
Broader Applications & Origins
Synthetic manufacturing processes create polyethylene glycols by reacting ethylene oxide with water or ethylene glycol. The resulting PEG-32 typically appears as a white, waxy solid or as flakes, depending on the specific supplier’s format. Outside of skincare, this material is widely used as a pharmaceutical excipient in ointments, suppositories, and tablet coatings due to its excellent biocompatibility and low toxicity.
Routine Integration
Synergies:
- Pairs effectively with traditional humectants like Glycerin and Sodium Hyaluronate to provide multi-level hydration.
- Works alongside thickeners like Xanthan Gum or Carbomer to create smooth, gel-cream textures.
- Enhances the delivery of water-soluble actives such as Niacinamide.
Conflicts:
- Universally compatible with most cosmetic ingredients and safe for all skin types.
Clinical Consensus & Safety
Dermatological reviews conducted by the Cosmetic Ingredient Review (CIR) Expert Panel have repeatedly concluded that polyethylene glycols are safe for use in cosmetics. While historical concerns existed regarding trace impurities like 1,4-dioxane, modern purification standards ensure these levels are far below safety thresholds for human health. Clinical data indicates that PEG-32 is non-irritating and non-sensitizing at the concentrations typically found in personal care products. However, caution is advised when applying PEG-based formulations to severely damaged or denuded skin, as increased absorption could theoretically occur in compromised barriers.
Is PEG-32 safe for acne-prone skin?
Yes, PEG-32 has a comedogenic rating of 0, meaning it does not clog pores. It is a water-soluble polymer that provides moisture without the heavy oils that often trigger breakouts.
Why is there a number “32” in the name?
The number 32 represents the average number of ethylene oxide units in the polymer chain. This specific length determines the ingredient’s physical state (a waxy solid) and its performance characteristics in a formula.
Is this ingredient considered “clean” or “natural”?
PEG-32 is a synthetic ingredient and is not classified as natural. While it is prohibited by some organic certification bodies like COSMOS due to its petroleum-derived origins, it is recognized as safe and effective by global regulatory authorities such as the FDA and the European Commission.