Solubilizer S-15 (CAS No.: 39464-69-2), with the chemical name PEG-40 Hydrogenated Castor Oil, appears as a colorless to slightly yellow transparent liquid. It belongs to the category of nonionic surfactants. Its molecule is formed by the polymerization of natural hydrogenated castor oil and ethylene oxide, with a molecular weight of approximately 2600, giving the product a unique amphiphilic structure. The most outstanding capability of this product is efficient solubilization — it can quickly disperse poorly soluble oily substances such as fragrances, essential oils, and pesticide technical materials uniformly into an aqueous system, forming a clear and transparent stable solution or microemulsion, fundamentally solving the common problems of turbidity and stratification in water-based products.
In terms of stability, Solubilizer S-15 performs excellently: it can maintain its chemical structure without degradation over a wide pH range and under high-temperature conditions. At the same time, it has good tolerance to hard water, acids, alkalis, and electrolyte solutions, allowing it to function stably even under harsh water quality conditions without the need for additional chelating agents. In addition, the product is derived from renewable natural raw materials. OECD 301B test data show that its 28-day biodegradation rate exceeds 60%, making it a readily biodegradable substance with extremely low aquatic toxicity (fish LC₅₀ > 100 mg/L). It meets the environmental trends of modern green chemicals and offers significant advantages especially in export-oriented formulations.
In terms of compatibility, Solubilizer S-15 is easily soluble in water and also has alcohol solubility. It can be flexibly compounded with various anionic, cationic, and other nonionic surfactants without being limited by ionic type. Its low-foaming characteristic also makes it particularly suitable for industrial cleaning and textile processing stages that require rapid defoaming or are not suitable for foaming. In scenarios such as spray application and high-speed printing and dyeing, it will not affect operational efficiency due to foam generation.
| Parameter | Typical Value/Range | Test Condition |
|---|---|---|
| Appearance | Colorless to slightly yellow transparent liquid | Visual |
| Ionic Type | Nonionic | — |
| HLB Value | 14~16 | — |
| Active Content | ≥99.0% | — |
| pH Value | 5.0~7.0 (1% aqueous solution) | 25℃ |
| Cloud Point | 65~75℃ | 1% aqueous solution |
| Density | Approx. 1.06 g/cm³ | 25℃ |
| Kinematic Viscosity | Approx. 550~650 mm²/s | 20℃ |
| Low Shear Viscosity | Approx. 700~900 mPa·s | 25℃ |
| Surface Tension | Approx. 35 mN/m | 1% aqueous solution, 25℃ |
| Critical Micelle Concentration (CMC) | ~0.1~0.5 g/L | 25℃ |
| Hydroxyl Value | 60~80 mgKOH/g | — |
| Acid Value | ≤1.0 mgKOH/g | — |
| Saponification Value | ≤2.0 mgKOH/g | — |
| Iodine Value | ≤2.0 gI₂/100g | — |
| Moisture Content | ≤1.0% | — |
| Flash Point (Closed Cup) | ≥100℃ | — |
| Foaming Characteristic | Low foaming | — |
| Water Solubility | Easily soluble in water | — |
1. Solubilization in Pesticide Formulations: In the formulation of emulsifiable concentrates, oil-in-water emulsions, and microemulsions, the recommended addition amount is usually 5%~20% (based on the total formulation). Utilizing its strong hydrophilicity with an HLB value of 14~16, it efficiently solubilizes oil-soluble pesticide technical materials into the aqueous phase, forming a transparent microemulsion system with excellent dilution stability. It is especially suitable for hard water dilution scenarios, significantly improving field efficacy.
2. Solubilization of Fragrances and Essential Oils in Daily Chemicals: In transparent shampoos, shower gels, toners, and other products, it is recommended to pre-mix the fragrance or essential oil with Solubilizer S-15 in a ratio of 1:1 to 1:3 before adding to the aqueous phase. This can quickly yield a clear, transparent finished product that remains stable without stratification during long-term storage. With low allergenicity and non-irritating properties (OECD 404 skin irritation test negative, OECD 406 sensitization test negative), it is particularly suitable for designing formulations for sensitive skin and baby care products.
3. Industrial Hard Surface Cleaning: In cleaning formulations for heavy oil stains on vehicles, machinery, etc., as a solubilizing and emulsifying component, it can quickly penetrate and remove mineral oils and hydrophobic dirt. The recommended dosage is 3%~10%, and better results can be achieved when used in combination with other anionic or nonionic surfactants. The low-foaming characteristic ensures smooth operation in high-pressure spray cleaning.
4. Textile Printing and Dyeing Auxiliaries: As a component of leveling agents and dye dispersing aids, it promotes uniform dispersion of disperse dyes in the dye bath and balanced adsorption on the fiber surface, effectively preventing uneven dyeing (color spots). The recommended dosage depends on the dye bath conditions and dye concentration, typically 0.5%~2% (based on the dye bath volume).