Solubilizer S-15, chemically known as PEG-40 Hydrogenated Castor Oil (CAS No.: 39464-69-2), is a nonionic surfactant synthesized by the polymerization of hydrogenated castor oil and ethylene oxide. It appears as a colorless to slightly yellow transparent liquid with a molecular weight of approximately 2600. The HLB value of this product ranges from 14 to 16, making it a hydrophilic surfactant. It is highly soluble in water and exhibits excellent chemical stability under a wide pH range, as well as in coexistence with acids, bases, and electrolyte solutions.
Its core performance parameters demonstrate good surface activity and solubilization capacity: the surface tension of a 1% aqueous solution (25°C) is approximately 35 mN/m, the critical micelle concentration (CMC) is between 0.1 and 0.5 g/L, and the cloud point is 65~75°C. The product has an active content ≥99.0%, moisture ≤1.0%, free alcohol ≤1.0%, and iodine value ≤2.0 (indicating extremely low unsaturation). These indicators collectively ensure high purity and batch-to-batch stability of the product.
From the perspective of safety and environmental parameters, the flash point is ≥100°C (closed cup method), posing no flammable risk under normal conditions. It is non-irritating to the skin, non-sensitizing, and has extremely low ecotoxicity (fish LC₅₀ and Daphnia EC₅₀ both >100 mg/L). The 28-day biodegradation rate is >60%, classifying it as readily biodegradable. The density is approximately 1.06 g/cm³ (25°C), the freezing point is below -10°C, and it remains in a stable liquid state during storage at temperatures between 5°C and 40°C.
| Parameter Item | Value/Description | Test Condition |
|---|---|---|
| Product Name | PEG-40 Hydrogenated Castor Oil | — |
| CAS No. | 39464-69-2 | — |
| Appearance | Colorless to slightly yellow transparent liquid | Visual |
| Ionic Type | Nonionic | — |
| Molecular Weight | Approx. 2600 | — |
| HLB Value | 14~16 | — |
| Active Content | ≥99.0 % | — |
| Moisture | ≤1.0 % | — |
| pH (1% Aqueous Solution) | 5.0~7.0 | 25°C |
| pH (5% Aqueous Solution) | 5.5~7.5 | 25°C |
| Density | Approx. 1.06 g/cm³ | 25°C |
| Cloud Point | 65~75 °C | 1% Aqueous Solution |
| Surface Tension | Approx. 35 mN/m | 1% Aqueous Solution, 25°C |
| Critical Micelle Concentration (CMC) | ~0.1~0.5 g/L | 25°C |
| Kinematic Viscosity | Approx. 550~650 mm²/s | 20°C |
| Low Shear Viscosity | Approx. 700~900 mPa·s | 25°C |
| Refractive Index | Approx. 1.466 | 20°C |
| Acid Value | ≤1.0 mg KOH/g | — |
| Saponification Value | ≤2.0 mg KOH/g | — |
| Hydroxyl Value | 60~80 mg KOH/g | — |
| Iodine Value | ≤2.0 gI₂/100g | — |
| Free Alcohol | ≤1.0 % | — |
| Freezing Point | < -10 °C | — |
| Flash Point | ≥100 °C (Closed Cup Method) | — |
| Foaming Behavior | Low Foaming | — |
| Heavy Metal Content | ≤10 mg/kg | — |
| Arsenic Content | ≤2 mg/kg | — |
| Chemical Stability | Stable in acid, alkali, and electrolyte solutions; hard water resistant | — |
| Hygroscopicity | Slightly hygroscopic | — |
| Packaging Specifications | 50kg plastic drum / 200kg plastic drum / IBC tote | — |
Solubilizer S-15, with a high HLB value (14~16) and low surface tension (approx. 35 mN/m), is particularly suitable for solubilizing fragrances, essential oils, and lipophilic active ingredients in aqueous systems. In pesticide microemulsion and emulsion formulations, the recommended dosage is typically 1 to 5 times the amount of active ingredient (adjusted according to the type and ratio of the oil phase). The solubilizer S-15 can be thoroughly mixed with the oil phase first, then water is added slowly to obtain a clear and transparent microemulsion or a stable and uniform emulsion.
In daily chemicals (transparent shampoos, body washes, toners, etc.), the recommended dosage is 3 to 8 times the weight of the fragrance or essential oil. The fragrance and solubilizer S-15 can be pre-mixed evenly before adding to the aqueous formulation to ensure the final product remains clear