From the perspective of chemical structure, its general molecular formula is RO(CH₂CH₂O)ₙH (where R represents a C16-C18 fatty chain, n≈40). The core structure consists of two parts: a hydrophobic long-chain fatty acid group (derived from stearic acid) that provides lipophilicity; and a hydrophilic polyoxyethylene chain segment composed of about 40 ethylene oxide units. This amphiphilic molecular structure, with one end hydrophilic and the other lipophilic, endows SG-40 with excellent oil-in-water (O/W) emulsifying ability and surface activity.
According to the product standards of Guoli Chemical, the active substance content of this product is as high as 99% or more. The highest-purity active ingredient—polyoxyethylene (40) stearate monoester—accounts for ≥90%, diester by-products are controlled within 5%, and residual free stearic acid and polyethylene glycol are extremely low (free alcohol ≤1%), ensuring excellent performance and safety.
| Parameter Item | Specification Value | Description |
|---|---|---|
| Chemical Name | Polyoxyethylene (40) stearate | INCI name: PEG-40 Stearate |
| CAS No. | 9004-99-3 | Globally unified chemical substance registration number |
| Molecular Formula | RO(CH₂CH₂O)ₙH (R=C16-18, n=40) | General structural formula |
| Active Content | ≥99% | Extremely high purity |
| Monoester Content | ≥90% | Core active component |
| Diester Content | ≤5% | By-product |
| Free Alcohol (PEG) | ≤1% | Extremely low residue |
| Ionic Type | Nonionic | Compatible with anionic/cationic/amphoteric systems |
| HLB Value | 16-17 | Highly hydrophilic, suitable for O/W emulsions |
Because its main component is high-purity polyoxyethylene (40) stearate with an HLB value of 16-17, it is highly soluble in water and is especially suitable for preparing oil-in-water (O/W) creams, lotions, shampoos, and other daily chemical products, as well as textile softeners, metalworking emulsified oils, and pesticide aqueous emulsions. Its nonionic nature allows it to exert stable emulsifying and dispersing functions in acidic, alkaline, and high-salt systems.