Solubilizer S-15 (PEG-40 hydrogenated castor oil) is a highly efficient nonionic solubilizer with an HLB value of 14-16, requiring no preheating or special pretreatment before use. The basic principle of use is: premix S-15 with the substance to be solubilized (fragrance, essential oil, oil-soluble pesticide technical, etc.) in proportion and stir evenly, then slowly add into the water phase while stirring, to spontaneously form a transparent and stable solution or microemulsion. Since the critical micelle concentration (CMC) of S-15 is only 0.1-0.5 g/L, it can rapidly form micelles to encapsulate oil molecules even at low concentrations, achieving high solubilization efficiency.
In actual operation, the order of addition has a significant impact on the solubilization effect. The recommended standard procedure is: first mix the solubilizer S-15 with the oil-soluble component to be solubilized and stir evenly (can be slightly heated to 30-40°C to accelerate mixing, but not necessary), forming a uniform oil-solubilizer mixture; then, under continuous stirring (recommended to use medium shear stirring, avoid high speed to introduce excessive bubbles), slowly inject this mixture into the water phase. If the system contains other water-soluble components (such as surfactants, humectants, salts, etc.), they can be pre-dissolved in the water phase before receiving the solubilizer-oil mixture. S-15 remains stable under different pH ranges (5.0-7.5) and hard water conditions, requiring no additional chelating agent protection.
Solubilizer S-15 is a colorless to slightly yellow transparent liquid, remaining liquid and not solidifying at low temperatures (below -10°C), but storage temperature is recommended to be kept between 5-40°C. If slight turbidity or separation occurs due to long-term low-temperature storage, it is a normal physical phenomenon; simply bring the product back to room temperature (20-30°C) and gently shake or stir to restore clarity, without affecting the use effect. Before use, it is recommended to conduct small-scale tests for each batch of oil-soluble component to verify the optimal ratio. Usually, a ratio of solubilizer to essential oil of 3:1 to 5:1 can obtain a clear and transparent aqueous solution.
| Parameter Item | Value | Description |
|---|---|---|
| Active content | ≥99.0% | High active ingredient concentration, economical dosage |
| HLB value | 14-16 | Strong hydrophilicity, suitable for O/W solubilization |
| Cloud point (1% aqueous solution) | 65-75°C | Maintains solubilization stability even at high temperatures |
| Critical micelle concentration (CMC) | ~0.1-0.5 g/L | Forms micelles at low concentrations |
| pH of 1% aqueous solution | 5.0-7.0 | Nearly neutral, good compatibility with formulations |
| Density (25°C) | Approx. 1.06 g/cm³ | Slightly heavier than water |
| Kinematic viscosity (20°C) | Approx. 550-650 mm²/s | Medium-high viscosity liquid, suggested for pumping |
| Water solubility | Easily soluble in water | Disperses and dissolves in cold water |
| Foaming characteristics | Low foaming | Suitable for scenarios requiring low foam formulations |
| Hard water resistance, acid/alkali stability | Excellent | Stable under wide pH and hard water conditions |
1. Pesticide formulations (emulsifiable concentrate, microemulsion, emulsion in water): Mix S-15 with the pesticide technical, solvent in the formula ratio evenly as the oil phase, and slowly add to water under stirring to spontaneously form a transparent or translucent microemulsion. It is recommended that the dosage of S-15 be 10%-30% of the total oil phase; the specific ratio should be determined by orthogonal experiments according to the polarity of the technical and the desired appearance of the formulation. S-15's excellent hard water resistance ensures that the formulation does not separate or precipitate during field dilution.
2. Household chemicals (transparent shampoo, body wash, toner): First premix S-15 with fragrance or essential oil at a ratio of 3:1-6:1, stir until uniform (can be slightly warmed), then slowly inject into the product's water-based matrix. Generally, the total addition amount of S-15 in the formulation is 0.5%-5%. If the fragrance dosage is 0.3%, the recommended S-15 dosage is about 1%-1.5% to obtain a clear and transparent finished product. S-15's low foaming property does not increase the foam volume of shampoo or body wash, and does not affect the product usage experience.
3. Industrial hard surface cleaners: Add S-15 at 1%-3% dosage together with other surfactants and auxiliaries directly into the water phase, stir evenly, and then introduce oily soil simulation tests. S-15 has excellent solubilization and emulsification effects on hydrophobic oils such as mineral oil and silicone oil; combined with anionic surfactants, it can significantly improve the overall detergency of the cleaner.
4. Textile printing and dyeing auxiliaries: As a component of leveling agent or penetrant, the recommended dosage of S-15 is 0.5-2 g/L of the working solution. Dissolve S-15 together with other auxiliaries in water for use; it has good solubilizing and dispersing effects on disperse dyes and finishing agents, helping to prevent color spots and improve dyeing uniformity.