Span S-85 (sorbitan trioleate) is a chemically stable nonionic surfactant that is not prone to deterioration under normal temperature storage. Its molecular structure contains unsaturated fatty acid ester chains (iodine value 75–85). Prolonged exposure to high temperature, humidity, or strong oxidizing environments may cause oxidative rancidity, affecting the product's color and emulsifying performance. Therefore, strict control of storage conditions is key to ensuring product quality and extending its service life.
Under cool, dry, sealed, and room-temperature conditions, unopened Span S-85 can typically be stored stably for 24 months. After opening, it should be used as soon as possible, and the container should be immediately sealed after each use to avoid prolonged contact with moisture and oxygen in the air. If the product shows significant color darkening, rancid odor, or delamination/cloudiness, it may have deteriorated and should not be used.
| Parameter | Value |
|---|---|
| Appearance | Amber to brownish yellow viscous oily liquid |
| Chemical Stability | Stable at room temperature; avoid strong acids and bases |
| Flash Point (Open Cup) | >200°C |
| Density (25°C) | 0.95-1.00 g/cm³ |
| Moisture | ≤1.5% |
| Recommended Storage Temperature | Room temperature range; avoid extreme high or low temperatures |
| Packaging Specifications | 50kg plastic drum, 200kg plastic drum, IBC tote |
Span S-85 has an HLB value of 1.8 and is a highly lipophilic water-in-oil (W/O) emulsifier. It is widely used in cosmetics, pharmaceutical ointments, metalworking fluids, and pesticide emulsifiable concentrates. It is recommended that users gently stir the product before use (increased viscosity at low temperatures is normal) and pre-dissolve/disperse it in the oil phase according to formulation requirements to fully utilize its emulsifying and dispersing effects.