OP-4SA nonylphenol polyoxyethylene ether ammonium sulfate (CAS number: 9051-57-4) is an anionic surfactant prepared by sulfation of nonylphenol polyoxyethylene (4) ether followed by neutralization with ammonium salt. Its unique molecular structure combines nonionic segments with anionic groups, giving the product outstanding emulsifying, wetting, and dispersing abilities. The product appears as a pale yellow transparent liquid with a density of 1.05~1.10 (25°C), a melting point below 0°C, and a low freezing point. Therefore, it may become turbid or stratify under low-temperature conditions, which is a normal physical phenomenon. It can be restored by warming to room temperature and stirring evenly, and the product performance is not affected.
In terms of solubility and stability, OP-4SA exhibits unique "amphiphilic" properties, readily soluble in oil and water. It maintains stable performance under weak acid to alkaline conditions, and especially remains stable in ≤10% NaOH solution, demonstrating excellent alkali resistance. It is well compatible with various inorganic salts, alkalis, and other auxiliaries, showing strong system adaptability, but it decomposes upon contact with strong acids and should be avoided. Additionally, the product has high foaming characteristics, with an initial foam height of ≥150 mm in a 0.1% aqueous solution. Its critical micelle concentration (CMC) is between 0.02~0.05% (mass fraction), meaning it can form micelles at low concentrations and rapidly reduce the surface tension of the solution (surface tension of 1% aqueous solution is 30~33 mN/m).
It is particularly noteworthy that the nonylphenol polyoxyethylene ether structure contained in OP-4SA is recognized as having potential environmental hormone effects, being harmful to aquatic life with long-lasting effects (H412). Therefore, during actual use and discharge, operators must strictly comply with environmental regulations to prevent any accidental release. The disposal of packaging waste must also be handled professionally according to relevant hazardous waste categories.
| Parameter Item | Technical Indicator (Data source: Guoli Chemical Database) |
|---|---|
| Product Name | Nonylphenol polyoxyethylene (4) ether ammonium sulfate |
| Ionic Type | Anionic |
| CAS Number | 9051-57-4 |
| Molecular Formula | C23H43NO8S (average n≈4) |
| Molecular Weight | Approx. 494 |
| Appearance | Pale yellow transparent liquid |
| Solid Content | 25~30% |
| Active Matter Content | ≥25% |
| HLB Value | 13.5 |
| Cloud Point | None |
| 1% Aqueous Solution pH (25°C) | 5.0~7.0 |
| 5% Aqueous Solution pH (25°C) | 5.0~7.0 |
| Density (25°C) | 1.05~1.10 g/cm³ |
| Kinematic Viscosity (25% solution, 25°C) | 50~200 mm²/s |
| Low Shear Viscosity (25% solution, 25°C) | ≤800 cP |
| Refractive Index | 1.38~1.42 |
| Flash Point | >100°C |
| Melting Point/Freezing Point | <0°C |
| Hygroscopicity | Easily hygroscopic |
| Surface Tension (1% aqueous solution, 25°C) | 30~33 mN/m |
| Critical Micelle Concentration (CMC) | 0.02~0.05% (mass fraction) |
| Penetrating Power (0.1% aqueous solution, canvas settling method) | Good (≤20 seconds) |
| Foaming Performance (0.1% aqueous solution) | High foaming (initial foam height ≥150mm) |
| Alkali Resistance Stability | Alkali resistant (stable in ≤10% NaOH solution) |
| Chemical Stability | Stable under alkaline conditions, decomposes with strong acids |
| Solubility | Readily soluble in oil and water |
| Hydroxyl Value | ≤5 mgKOH/g |
| Saponification Value | ≤5 mgKOH/g |
| Acid Value | ≤3 mgKOH/g |
| Amine Value | ≤2 mgKOH/g |
| Iodine Value | ≤1 gI2/100g |
| Moisture Content | ≤1.0% |
| Free Alcohol | ≤2% |
| Heavy Metals (as Pb) | ≤10 mg/kg |
| Arsenic (As) | ≤2 mg/kg |
OP-4SA has comprehensive performance and a wide range of application scenarios. Core usage suggestions are as follows: