The active ingredient of Oleth-5 (INCI name: Oleth-5, CAS: 9004-98-2) is Oleth-5. This product is synthesized by the addition polymerization of naturally sourced oleyl alcohol (cis-9-octadecenol) with 5 moles of ethylene oxide (EO), belonging to the typical fatty alcohol polyoxyethylene ether nonionic surfactants. Its content (solid content) is not less than 99%, free of free phosphoric acid, amines, or other inorganic salt components, making it a high-purity single main component product. It appears as a colorless to light yellow transparent liquid with good chemical stability.
From a molecular structure perspective, its hydrophobic end is a long carbon chain unsaturated oleyl group (C18H35-), and its hydrophilic end is a polyethylene oxide chain with an average polymerization degree of about 5 (-(CH2CH2O)5H), with a molecular weight of approximately 490. This specific short EO chain structure gives it an HLB value of about 9, making it poorly soluble in water and an oil-soluble (W/O type) emulsifier. The product is stable at room temperature, with a flash point above 150°C, and features low foaming, acid and alkali resistance, and hard water tolerance.
| Parameter | Specification |
|---|---|
| Chemical Name | Oleth-5 |
| INCI Name | Oleth-5 |
| Molecular Formula | C18H35O(C2H4O)nH, n≈5 |
| Molecular Weight | ~490 |
| Active Content | ≥99% |
| Free Alcohol Content | ≤1% |
| Water Content | ≤1.0% |
| Appearance | Colorless to light yellow transparent liquid |
| Ionic Type | Nonionic |
| HLB Value | 9 (Oil-soluble) |
| Iodine Value | 50~65 gI2/100g (Unsaturated) |
Given that this product has oleth-5 as its single main component, it is primarily used as a W/O (water-in-oil) emulsifier and co-emulsifier. In cosmetic creams, lotions, and sunscreen products, it provides excellent formulation stability and spreading skin feel. In industrial cleaning, textile scouring, metalworking fluids, and pesticide emulsifiable concentrates, due to the short EO chain in its molecular structure, it exhibits strong oil emulsification and penetration wetting capabilities, serving as a core functional component in these fields. This product is easily soluble in oil. If used in aqueous systems, it is recommended to combine with other high-HLB emulsifiers to form a composite emulsification system.