Physicochemical Technical Parameters of Emulsifier S-185/O-5
Detailed Description
Emulsifier S-185/O-5 (chemical name: fatty alcohol polyoxyethylene ether, alias: stearyl alcohol polyether-35, PEG-35 stearyl alcohol ether, CAS number: 68439-49-6) is a high-performance nonionic surfactant, appearing as a white to light yellow paste. Its molecular structure and physicochemical properties endow the product with excellent emulsifying, wetting, dispersing, and solubilizing capabilities, along with outstanding resistance to acids, alkalis, and hard water, and good compatibility with various ionic and nonionic surfactants.
Under the production process of China Guoli Chemical, this product achieves high active content (≥99%) and low moisture (≤1.0%). It is widely used as an efficient emulsifier and dispersant in multiple industrial fields. The following technical parameters are derived from the product database test data and product standards of Guoli Chemical.
Technical Parameters
Basic Physicochemical Properties
| Parameter | Typical Value / Description |
|---|
| Chemical Name | Fatty alcohol polyoxyethylene ether (stearyl alcohol polyoxyethylene ether) |
| Trade Name / Alias | Polyoxyethylene (35) stearyl ether, stearyl alcohol polyether-35, PEG-35 stearyl ether, Emulsifier S-185 |
| CAS Number | 68439-49-6 |
| Ionic Type | Nonionic |
| Molecular Formula | RO(CH₂CH₂O)ₙH (R=C16-18, n=35) |
| Molecular Weight | Approx. 1800 |
| Appearance (25°C) | White to light yellow paste |
| Active Content | ≥99% |
| Moisture | ≤1.0% |
| pH Value (1% Aqueous Solution) | 5.0-7.0 |
| pH Value (5% Aqueous Solution) | 5.0-7.0 |
| Density (20°C) | ≤1.0 g/cm³ |
| Melting Point | Approx. 30-35°C |
Functional Indicators
| Parameter | Typical Value / Description |
|---|
| HLB Value | 16-17 |
| Cloud Point | >100°C |
| Hydroxyl Value | 30±5 mgKOH/g |
| Acid Value | ≤1.0 mgKOH/g |
| Iodine Value | ≤2 gI₂/100g |
| Saponification Value | None |
| Amine Value | None |
| Free Alcohol Content | ≤1.0% |
Surface and Interfacial Properties
| Parameter | Typical Value / Description |
|---|
| Surface Tension (0.1% Aqueous Solution, 25°C) | Approx. 30-35 mN/m |
| Critical Micelle Concentration (CMC) | Approx. 10⁻⁵ - 10⁻⁴ mol/L |
| Penetration Power | Medium |
| Foam Characteristics | Low to medium foaming |
Solubility and Compatibility
| Parameter | Typical Value / Description |
|---|
| Water Solubility | Easily soluble in water |
| Solubility in Organic Solvents | Easily soluble in organic solvents such as ethanol and acetone |
| Chemical Stability | Resistant to acids, alkalis, salts, and hard water; chemically stable |
| Alkali Resistance | Excellent |
Viscosity and Thermodynamic Properties
| Parameter | Typical Value / Description |
|---|
| Kinematic Viscosity (10% Aqueous Solution, 40°C) | Approx. 300-500 mm²/s |
| Low Shear Viscosity (40°C) | 300-500 mPa·s |
| Refractive Index (40°C) | Approx. 1.46 |
| Flash Point | >150°C |
| Hygroscopicity | Hygroscopic |
Safety and Environmental Parameters
| Parameter | Typical Value / Description |
|---|
| Heavy Metal Content (as Pb) | ≤10 mg/kg |
| Arsenic Content (As) | ≤2 mg/kg |
| Free Phosphoric Acid | None |
| Monophosphate Ester | None |
| Diphosphate Ester | None |
Application Recommendations
Emulsifier S-185/O-5, with its HLB value as high as 16-17, is particularly suitable for O/W (oil-in-water) emulsification systems. It is recommended to be used at 2%-8% in pesticide emulsifiable concentrates, microemulsions, and emulsion concentrates; at 1%-5% in industrial cleaning agents; and at 3%-10% in metalworking fluids as an emulsifying and lubricating component. The specific dosage should be optimized through experiments based on the formulation system and target emulsified oil phase content.
This product is a paste at room temperature. Before use, it can be slightly heated (approx. 35-40°C) to improve flowability for accurate weighing and dispersion. During preparation, it is recommended to dissolve it in the water phase first or premix with the oil phase before adding water for phase inversion; both methods can achieve good emulsification effects.
Precautions
- The product is hygroscopic; after opening, it should be sealed promptly to prevent moisture absorption and caking.
- Avoid excessive temperature during melting or heating; prolonged exposure above 80°C may cause color deepening.
- Storage temperature is recommended to be maintained at 5-40°C; at low winter temperatures, the paste may harden, and it can be restored to its usable properties after warming.
- Avoid direct contact with skin and eyes during operation; use protective gloves and goggles.
